Matt Harvey and Doing It the Hard Way

In a Friday matinee, the sensational Matt Harvey will take the mound for the Mets against the Cubs in Chicago. Though the Cubs are hardly to be considered a daunting opponent, Harvey’s right-handed, and the Cubs hitters to be worth a damn so far are the left-handed Anthony Rizzo, the left-handed Luis Valbuena, the left-handed Nate Schierholtz, and the left-handed David DeJesus. At a glance, you might figure this could be a tougher matchup for Harvey than it seems.

And it might well play out that way, because, baseball. The other day, after Dave Cameron ripped the Mariners for starting Raul Ibanez against CC Sabathia, Ibanez singled and homered. Hilarious! There’s absolutely not a single way to know how a given player is going to perform on a given day. Harvey might be aces, Harvey might be awful, or he might be somewhere in between. But if we’re going to think about the probability, we shouldn’t be worried about Harvey facing the Cubs’ lefties. Because to this point in his career, Harvey’s been doing something unusual.

Most everybody’s familiar with the concept of platoon splits, and most of those most understand that it can take some time for platoon splits to stabilize. An awful lot of time, in some cases, depending on the statistics you’re dealing with. Observed reverse platoon splits usually aren’t real reverse platoon splits on true talent. Hitters will generally be better against opposite-handed pitchers, and worse against same-handed pitchers. It’s important not to overreact to a small-sample platoon-split curiosity.

And Matt Harvey’s started only 18 games in the major leagues, facing 451 batters. Right away, we know it doesn’t matter what we look at — it’s going to have a small sample involved. But that doesn’t make the information meaningless, and things like strikeout rate stabilize faster than a lot of other things. Harvey, so far, has allowed a .247 wOBA to righties, and a .234 wOBA to lefties. That’s weird and exceptional. But it’s not just noise — the BABIPs are low for both. And the strikeouts are particularly notable.

Of 206 righties, Harvey has struck out 51, or 24.8%. That’s over his limited career. Of 245 lefties, Harvey has struck out 81, or 33.1%. One might also note that Harvey has walked six more righties than lefties despite the lower PA total, and all in all, Harvey is showing a hell of a split, in the other direction. A split based not only on wOBA, but also on more meaningful core statistics.

In case you’re dissatisfied, we also have some minor-league information on Harvey. We turn to Minor League Central, which offers Harvey splits for 2011-2012. Of 552 minor-league righties, Harvey struck out 115, or 20.8%. Of 488 minor-league lefties, Harvey struck out 153, or 31.4%. And again, Harvey had a slightly lower walk rate against lefties, too. We have more than two years of professional evidence that Matt Harvey could have a reverse platoon split, at least in terms of strikeouts.

If it’s pitch information you’re after, here’s a table you might appreciate:

Split	Strike%	Swing%	Contact%
minors, RHB	60%	42%	79%
minors, LHB	64%	47%	70%
majors, RHB	62%	46%	78%
majors, LHB	66%	51%	71%

More strikes to lefties, more swings by lefties, less contact by lefties. The splits hold true, and now this is something to take seriously.

I was curious about the difference between Harvey’s strikeout rate against lefties and his strikeout rate against righties. The difference we have is 8.3 percentage points. I looked at everybody who has at least 50 innings pitched against both lefties and righties since 2008, then I narrowed the pool to only right-handed pitchers, then I narrowed the pool to only right-handed starters. I ordered by strikeout-rate difference, in the reverse-platoon direction. The top 5:

1. Matt Harvey, +8.3% against lefties
2. Miguel Gonzalez, +6.7%
3. Vance Worley, +5.5%
4. Mike Mussina, +5.2%
5. Gil Meche, +4.7%

Harvey beats everyone else, among his peer group. For whatever it’s worth, four right-handed relievers have shown a bigger difference, namely Jordan Walden, Ernesto Frieri, Scot Shields, and Kevin Gregg. Interestingly, all four have at least somewhat recently pitched for the Angels. The Angels would love to have Matt Harvey, too, but then the Angels would probably love to have any kind of half-decent starter. Like Ervin Santana, or Dan Haren.

Now, this is either a thing to celebrate or a thing to lament. Based on your perspective, Harvey is either performing incredibly well against lefties, or not well enough against righties. I can’t imagine anyone’s actually troubled, though, given the overall package, and we can wrap up with an attempted explanation. Righties get mostly fastballs and sliders from Harvey, with a few other pitches sneaking in when Harvey’s ahead. Lefties get mostly fastballs, curves, and changeups, and sliders creep into the picture when Harvey’s ahead. But this doesn’t say enough. Righties have made 83% contact against Harvey’s fastball. Lefties have made just 66% contact against the same pitch. Fastballs are supposed to be a pitcher’s most basic pitch, and Harvey’s is a putaway weapon.

Of Harvey’s 51 strikeouts of righties, 22 have come on his fastball and 18 have come on his slider. Of Harvey’s strikeouts of lefties, 48 have come on his fastball and 14 have come on his changeup. Below, look at a strikeout slider against a righty and a strikeout changeup against a lefty:

But Harvey’s signature weapon is probably his high heat, which has just given lefties fits. It’s interesting that we’ve seen Frieri’s name, since he does the same thing with his fastball. This might be something to explore later on. But for now, we’ll settle for .gifs of pure unhittable gas:

As with everything in baseball, a real explanation here would be complex. There’s a lot that’s gone into Matt Harvey establishing something of a reverse platoon split. It helps that he has a change and a curve, both of which are helpful against opposite-handed batters. The biggest key might well be Harvey’s high fastball, which might be an underrated weapon for righties against lefties, and for lefties against righties. And ultimately, even if the proposed explanation is way off, here’s what we know for certain: Harvey has had a weird, reverse platoon split. We see it in his minor-league numbers, too. Matt Harvey’s an interesting guy. Even more so than you probably already thought.