One more thing to add about the effect of a closed dome — there is another variable used to describe movement in pitch f/x, called “break length”, which is defined as:
“…the greatest distance between the trajectory of the pitch at any point between the release point and the front of home plate, and the straight line path from the release point and the front of home plate.”
Here is a graphic ripped off from a John Walsh article showing what that means:
Basically, if you threw a curveball that instead of travelling in a perfectly straight line from your hand to the catcher’s glove, went ten feet up and then back down into the mitt, the break length of that pitch would be 10 feet. It doesn’t matter if it breaks down or sideways, just how “loopy”, or “bendy” the breaking pitch is. I rarely end up using this number, because I’m never sure if that’s a good thing or not. In the case of sliders, it’s a bad thing: you want a tight slider that looks like a fastball until the last minute. In the case of most curves, it’s a good thing: the more knee-buckling, the better.
You have to just ignore the early spikes on these graphs because it’s based on a super-small sample size of a single game at 1 and 3 mph, but if we compare wind magnitude (mph) to break length (inches), there is a clear and sustained connection between the ‘loopiness’ of Dickey’s knuckler and how hard the wind is blowing:
That’s what you might expect from a pitch that is dependent on interacting with air currents for its movement, but for some reason it also leads to batters taking more cuts:
And especially in very windy conditions, getting way more hits:
Again, each knuckleball is so random it’s mostly speculation exactly what is making them more appealing to swing at and easier to get a hit off, but this is another indication that a closed dome really helps R.A. — if only to escape the nightmare of a stiff breeze. Perhaps, as has driven the modern trend away from big breaking balls to splitters and cutters (and Dickey’s Cy Young season being due to a harder knuckler with less movement on it) pitches that break a lot are impressive, but not as effective against major-leaguers as those that seem to be hittable and then dart away at the last moment.
There was a lot of speculation last year about the effect of the dome on R.A. Dickey’s knuckleball, to the point where the dome was closed on a perfectly lovely fall day for his last start after Dickey made some noise in the media about wanting it that way. While Dickey seems like a guy who is exceptionally in touch with his craft, and a quick look at his numbers seems to support the idea, Alex Anthopolous is right to grumble about sample size and Dickey’s early-season injury making ERA comparisons questionable at best — especially since a major fight with the MLB is looming if the Jays start closing the dome next year on sunny days in June.
It has been rumoured that knuckleballers thrive in domes since the days of Wakefield crushing the Jays, but the details have always been vague. I’ve heard humidity and the wind raised as possible factors, but never a clear explanation of why, or whether the pitch is more controllable, less predictable, or has more movement on it inside a dome. Fortunately, pitch f/x records whether the roof was open or closed, as well as the wind and direction, so it’s possible to drill down and look at the results of individual pitches to investigate some of the theories floating around.
Theory 1: R.A. Dickey has better control over his knuckleball when the dome is closed.
Sounds plausible — if the knuckleball wasn’t quite so impossible to control it would be the best pitch ever, so maybe in calmer air the pitch is not quite as difficult to get over the plate. As Tom Candiotti said:
“It’s really a great place to pitch,” former Major Leaguer Tom Candiotti said of Rogers Centre. “I pitched with the roof open, I pitched with the roof closed, and I always preferred the movement of the ball and the consistency of the movement with the roof closed because it was the same every inning.”
However, there was absolutely no difference last year in the percentage of knuckleballs that ended up crossing the plate in the strike zone with the roof open compared to closed:
|Dickey’s Knuckleball Accuracy|
|Conditions||In zone %|
|2013 – Away Games||48|
|2013 – Dome Open||49|
|2013 – Dome Closed||49|
For most pitchers, this would not be enough to close the book on ‘control’– you really need to get into how close to the edges of the strike zone, or the spots that the pitcher is actually aiming for. But even Dickey acknowledges that at most he is starting his knuckler in slightly different regions of the strike zone and then letting the pitch do its random thing from there. You’d have a hard time convincing me that Dickey is somehow ‘hitting his spots’ within the strike zone better due to a more consistent knuckleball, but not throwing any more pitches in the zone overall.
Theory 2: Dickey’s Knuckleball is harder to hit with the roof closed.
So if the movement isn’t more consistent, is it just plain nastier? I think misses per swing (with fouls taken out of the equation since there is no way to differentiate between a foul tip and a 400-foot drive that hooked just foul) is the best measure of how difficult it is to make contact with an offspeed pitch. Yes, deception is important, and getting hitters to chase pitches out of the strike zone can be as effective as throwing a pitch with incredible movement. But it all balances out very well into one number — if a major league hitter decides to swing at an offspeed pitch and comes up completely empty, that pitch had quality movement, whether it was down the middle or bounced in the dirt. And Dickey generated more misses with the dome closed last year:
|2013 – Away Games||40|
|2013 – Dome Open||32|
|2013 – Dome Closed||38|
Interesting, but a difference of 6% is not that significant, and Dickey’s numbers were just as good on the road in 2013. However, if we’re talking about swings and misses, remember that Dickey throws two hard knuckleballs (in addition to his 65 mph floater), one in the low 70’s and one in the high 70’s that he tends to use as a strikeout pitch. As I showed before last season started, it was throwing so many more of the high-70’s knuckler that made his strikeout rate go through the roof last year, and while pitching through injury early in the season, that pitch was largely missing from his repertoire. So here are his swing-and-miss numbers for Dickey’s knucklers that were thrown faster than 76 mph:
|Dickey’s knuckleballs > 76.0 mph|
|Year/Conditions||In Zone %||Miss/Swing %|
|2013 – Away Games||43||31|
|2013 – Dome Open||47||33|
|2013 – Dome Closed||53||48|
Now that’s something. It might not seem like it, but a 15% difference in miss rate is a TON. For example, the average miss rate for curveballs last year in the majors was 35.5%. The best curveball in the league (over 200 thrown) was 52%. So the difference in terms of swing-and-misses for Dickey’s hard knuckler with the dome closed compared to either being on the road, or with the dome open, was just about the same as between a run-of-the-mill curveball and the best one in the league.
Verdict: Very much so.
Ok, but why? Swings and misses are a lot better than ERA, but results are never quite enough to be totally sure — maybe he was more effective at home for other reasons like the mound, the home crowd, or he just happened to be facing poorer teams (correlation does not imply causation, for the statheads out there). But if there is proof of his knuckleball moving in a fundamentally different way under dome-closed conditions, that’s much more compelling and puts to rest any doubts remaining about the sample size or other factors.
So now let’s look at the average movement under different wind conditions, compared to those inside the dome. Pitch f/x movement is always measured in comparison to a spinless pitch, so the average for a knuckleball averages around 0 for both x (horizontal movement in inches, with positive values representing movement towards a left-handed batter) and y (vertical movement), since the random movement in all directions that the knuckleball takes on from there cancels out.
(Keep in mind that this is simply a measure of where the pitches tend to end up crossing the plate compared to where they would have if nothing was happening at all. This doesn’t have anything to say about when or how they flutter on the way to the plate.)
|Effect of wind on Knuckleball movement and results|
|Wind||PFX||PFZ||In Zone %||Miss %|
|Right to Left||0.05||0.03||0.50||0.30|
|Left to Right||-0.26||0.57||0.49||0.33|
So while a crosswind seems to have no particular (at least consistent) effect, on average Dickey’s knuckleball is more likely to have almost two inches more of up-and-away movement with the dome closed than in other wind conditions (the results are even more compelling if we only look at Dickey’s 76+ mph knuckleballs again: [pfx: -0.24 pfz: 1.35 with the dome open vs. pfx: 0.80 pfz: 2.15 with it closed]. As I showed in a previous article, that direction of movement is by far the most deadly: “Hitters swing through them almost twice as often as ones that sink down and in, and get fewer hits when they do make contact.”
There may be other reasons, but that makes sense considering that it’s a type of movement that is not seen in any other pitch. Sometimes Dickey’s knuckleball ends up having similar action to a changeup, or a slider, or even a rising fastball. But no other pitch in the world moves in that direction (Mariano Rivera’s cutter came the closest)
Theory 3: Higher humidity (with the dome closed) is good for the knuckleball.
Dickey has mentioned humidity as a factor several times, and In an interview with Michael Morrissey, Dickey gives his theory on how it helps the knuckle:
As expected, Dickey noted that domes and places with high humidity are good environments for his knuckleball. Domes are good because of the lack of wind. High humidity is good because “the seams grip the air better.”
But then in another interview, Dickey seems to suggest that it has an adverse effect (although he could be referring to overly humid conditions making it hard for him to get the proper grip, as most pitchers see their K rates drop at very high temperatures, most likely due to sweat):
Yes, a controlled climate is (desirable) and a dome offers you that,” Dickey said. “But if it’s been open all day and then it’s closed at game time, all that humidity (gets) stuck there and that’s not good (for a knuckleball).”
Anyway, humid air is actually less dense than normal air (seems backwards but is true), so I don’t buy the idea that it would grip the seams more. And if anything, less drag should make the knuckleball have less movement (imagine pushing a beachball through water compared to air). But another thing that would cause less resistance on the ball is having the wind at Dickey’s back — which is the other number that pops out from the above movement table as causing Dickey’s knuckleball to rise. (Wind “in” on the above table, which is a combination of in from right, left, and centre field — if we isolate down to wind coming straight in from CF, pfz rises even higher to 2.16).
This supports the idea that higher humidity inside the dome makes Dickey’s knuckleball rise and become harder to hit, in much the same way that wind at his back does — but there’s something else with the dome closed that gives it sideways movement as well, away from right-handed batters. Or that’s my theory, anyway — for a much more rigorous look at the physics behind what makes the knuckleball do its thing, check out Alan Nathan’s site.
Verdict: Highly probable, but best left to real physicists.
- While it might have some kind of subtle effect, Dickey’s knuckleball is not more ‘accurate’ in any meaningful way with the roof closed.
- Dickey’s knuckleball gets far more swings and misses when it rises/floats, especially up and away from right-handed batters.
- He can throw it harder to make that happen but also gets more lift if he has the wind at his back, and more lift + movement away from right-handed batters with the roof closed.
- The effect is much more pronounced on Dickey’s upper-70’s knuckleball than his lower-70’s offering, or his 65mph floater.
- The results are significant enough that if Dickey was starting for the Jays in a critical game there is a strong argument to be made in favour of closing the dome. (Or maybe a humidifier promotion? Hand fans for everyone in centre field? Starting the “hurricane” instead of the “wave”? The possibilities are endless…)
It’s mostly just Richard Griffin twisting his words into something bigger than they are, but the talk about how the Steroid Era hurt him and the Blue Jays is all rather rich coming from Pat Hentgen:
“When I look back on it, no question about it, I definitely gave up more runs, I definitely feel like it cost me more earned runs and it cost our team more runs because of it.”
In 1998, Pat Hentgen had the worst full season of his career (5.17 ERA), but still won 12 games — helped in no small part by one of the greatest achievements in juicing of all time: a 33-year-old Jose Canseco hitting 46 home runs as a member of the Blue Jays. It’s hard to imagine how any other team could have been helped more by Steroids that season, especially considering the Jays’ ace was Roger Clemens in his juicing prime.
Without ‘roiders, the Jays’ would not have been in the race, would not have won the most games of any Jays’ team since winning the World Series, and Hentgen would not have had a winning record. Other than the pure satisfaction of winning, it’s not a stretch to say that being on a team that was juiced to the gills prolonged Hentgen’s career and got him more money at contract time despite his best days being behind him.
I like Pat Hentgen, and I certainly am not suggesting that he should have taken on the era single-handedly. But when you play alongside and reap the rewards of two of the most obviously guilty and highly successful juicers of all time, and in your own words “just blend in and go with the flow”, you’ve lost all right to complain or take the moral high ground years later. The Jays’ history is just as dirty as any team’s, if not more, and any attempt to rewrite our dirty history is nauseating — even a little laughable after so enthusiastically embracing Melky Cabrera.
Sometimes you have to step back and think about what the data you’re crunching really means. Shi Davidi’s latest piece using pitch f/x comes to the conclusion that pitchers are “getting the calls” because more balls in the zone are called strikes than the other way around. But let’s think about that for a millisecond, shall we?
There’s an area around on the fringe of the strike zone where blown calls get made. Every strike is by definition no more than 10 inches away from that danger zone (because it’s somewhere in the zone) while balls can be anywhere — bounced, two feet outside. If there a super simple call to be made, it was a ball.
So by using the overall number of balls and strikes (instead of, say, only pitches within 3 inches of the border) that includes all pitches close and not to find a percentage of incorrect calls, all this “study” has really proven is that strikes are more likely to be blown calls, which is something logically obvious and not stunning at all. If you actually do the hard work and concentrate only on fringe pitches (or something — the classic John Walsh article at the Hardball Times graphed the overall % of pitches called strikes and vice versa by inches from the plate to find where they crossed on both planes), you find the real zone is slightly larger than the rulebook zone, and hitters generally get the shaft a little. Just like everybody thought. Shi, you’ve got a bunch of major-leaguers to go back to and unconfuse (while pleading they give the new technology another chance, please).
The one interesting thing to be gleaned from this outrageous mess is a corroboration that the corners are generally clipped — mid/away is where all the “called strikes out of the strike zone” (I would call them “extra strikes”) are, and down and away are where most of the extra balls are. But then Shi ignores that fact when coming to the rest of his conclusions:
Mauer, in fact, gets the fifth fewest ball calls on pitches in the zone at 11.96 per cent. Oddly, Blue Jays slugger Adam Lind, widely credited for his discipline this season, gets the least calls in this category at 10.24 per cent.
What about their drastically different swing rates? What this actually reflects is how many close strikes on the corners a hitter takes (since that’s almost exclusively where ‘extra balls’ come from, as shown by Shi’s own charts). Lind may have been credited with taking more walks this year, but his discipline hasn’t improved much — so he fouls off or puts in play balls placed right on the corner where umps are more likely to not call them, and doesn’t get as many of them to begin with as a player of Mauer’s calibre. Trying to guess how he is being treated by the umps without considering the flip side (how many strikes out of the zone are called on him — could be just as low), or how often he swings the bat, is pointless.
Janssen’s percentage of pitches in the strike zone called for balls is 10.9 per cent, nearly half the big-league average, while his ratio for strikes outside the zone is 15.4 percent, more than double the average.
In much the same way, you have to consider at where these pitches are, instead of assuming that you can lump them together and the distribution is average. That’s not a sign that the umpires are giving him calls, it’s a sign of where Janssen is throwing the ball — he mixes his straight fastball and cutter at the belt and just on or off the plate instead of purely hunting for the corners with sliders, etc. It’s a great approach because it takes advantage of where umpires give the calls — but we’ve got a chicken and egg thing going here. Casey gets better calls because he knows (or his natural approach has blundered across) where to go for them — they aren’t given to him because the umpires respect him.
It goes on and on…one blatant misinterpretation to fit the pre-existing narrative after the other. I know I sound like a statistical crank here, but sometimes you gotta question if the first thing that pops into your mind that makes for a great story is right, or if something else could be causing the phenomenon. I cannot tell you how hair it makes me lose to listen to Zaun completely dismiss the system and it’s “laser-guided gizmos” because the dome vibrates when it gets loud, and then watch Shi absolutely brutalize the data like this. Way to make science look stupid, guys. It’s not.
(Incidentally, the one issue that almost gets a complete pass here is that the strike zone is of course three-dimensional, while the graphic you see on TV is just the front edge. Apparently before giving the results back to the umpires, MLB cleans up the technically-should-be-strikes that just clip the edges/corners of the zone because everyone knows they never really called. On the flip side, there are clearly some pitches that cross the front of the plate just off that curve or tail to clip the back and should rightly be called strikes. That’s what Zaun should be grumbling about.)
Some players simply will never have the ability to recognize and lay off tough pitches that start in the zone and wind out of it. I get that. It is entirely possible to have a reasonable career that is based on hitting first pitches and mistakes very, very, far, and accepting that once you get behind in the count it’s going to take a miracle to get on base.
But other times, the balance between taking strikes and chasing balls becomes so lopsided that opposing pitchers can adjust their entire pitching strategy to take advantage of a player. Without the fear of a potential walk, there isn’t the same need to get ahead with the first pitch, or ‘give in’ in a hitter’s count with a fastball, and a hitter just stops getting reasonable pitches to hit, ever. In the same way that it pays sometimes to bunt or else the opposition will play way back on the grass and gain more than you lose by bunting, sometimes you just have to take a close pitch that might very well be a strike just so the league knows you’re capable of it.
Case in point: J.P. Arencibia. On 3-2 counts, most hitters are going to see somewhat more strikes with the threat of a walk looming. But now that every scouting report on him is just a giant yellow highlighter down his walk, swing, and miss rates, only 46 percent of full-count pitches have been in the strike zone (down from 55% last year — and not surprisingly, he’s missing them at 48%, up from 32%). Which brings to mind a novel way to “make the adjustment” back at the league: never, ever, swing with the count full.
Using his current strategy of “attempting to use his baseball skills to avoid striking out” in full counts, JP has struck out 19 times and walked 6. He also has three singles and two doubles. If he was instead using the revolutionary approach of “keeping the bat on your damn shoulder at all times”, of the 46 pitches he saw in those counts, 21 were in the zone and 25 of them were out. So, if we forget that some of those pitches happened in the same at-bats due to foul balls:
Using skills to reach base: 19 strikeouts, six walks, 10 outs in play, three singles and two doubles, vs:
Doing absolutely nothing: 21 strikeouts, 25 walks, zero balls in play.
OF COURSE THIS IS AN ABSURD SUGGESTION. But no more than the fact that not using his bat in full count situations would not seriously affect how often Arencibia strikes out on 3-2, and that somehow convincing the league that he was in the batter’s box ready to do his thing when he was actually watching the payoff pitch from his usual position crouched behind the plate would more than double his walk rate overall. His average would fall from .218 to .215, but his OBP would soar from the current league-worst .253 up to .295. And with JP’s pop, that’s a major-league catcher!
The Jay Land (With apologies to T.S. Eliot)
APRIL is the cruellest month, losing
Games out on the cold land, freezing
Ligaments and desire, whiffing
Dead bats causing spring pain.
Winter kept us warm, covering
T.O. in forgetful snow, feeding
Too much hope with press releases.
The offseason surprised us, coming towards the ‘dome
With a shower of money; we stopped in the blizzards,
And went on in sunlight, into the beer garden,
And drank pitchers, and talked for hours.
Buehrle, Johnson, Reyes, Dickey, Cabrera, it is done!
And when we were children, listening on the radio,
My friend’s, he took me out for some hacks,
And I was terrible. He said, Jon,
Jon, swing more softly. And out it went.
In the fields, there you feel free.
I read, much of the season, and go to Cuba in the winter.