The renewed evolution of Scott Kazmir

Baseball players always change. They don't really have a choice — if they stayed the same, the rest of the league would catch on and take advantage of their stagnation. Whether it's reworking their approach at the plate, getting a tick faster on defense, or (hint) incorporating a new pitch into their repertoire, they always stay a step ahead of the competition.

Perhaps no one can testify more to this than Scott Kazmir. After coming to Tampa Bay in a rather one-sided trade, he blossomed into an ace pitcher and brought his team out of mediocrity. Within a few years, however, the power behind his pitches began to deteriorate, and the results vanished with it. When the Angels cut him in early 2011, his story appeared over.

Then, like the proverbial phoenix, Kazmir rose from the ashes of his career to start again. First with the Indians, and now with the Athletics, he's again proven his mettle and come out on top. But the methods behind his success have changed — from before his comeback and during it as well. We'll look at three different versions of Kazmir to evaluate these alterations: 2007-2008, 2013-2014, and 2015.

Let's start with Kazmir's defining pitch: his fastball. In the days of yore, Kazmir possessed an electric four-seamer that he blazed by batters with regularity. Across 2007 and 2008 (the first two years of the PITCHf/x era), it resulted in a whiff 12.8% of the time he used it — more than double the 5.6% baseline for the pitch, and the main reason why he paced the AL in strikeouts over that span.

Kazmir's fastball velocity soon waned, dropping from 92 to the upper 80s, and he consequently washed out of baseball. As detailed by Kyle Boddy at the Hardball Times, he ended up regaining that bite by changing up his delivery; from there, he picked up where he left off, leaning heavily on his 92mph four-seamer. But it didn't deceive the opposition like it once did, causing a swing-and-miss in only 8.9% of its appearances from 2013 to 2014. The cause of that? Location, location, location:

Old Kazmir threw the fastball high and saw more whiffs with it. New Kazmir kept it down more and saw more contact with it.

But wait! It gets weird. See, the 2015 iteration of Kazmir owns the same fastball, in terms of velocity, that the 2007-2008 one did and that the 2013-2014 one did. The only difference is he now garners much more whiffs on it — to the extent that he did in his glory days:

Year(s)	Four-seam velocity	Four-seam SwStr%
2007-2008	92.8	12.8%
2013-2014	93.0	8.9%
2015	93.1	13.6%

His location of the pitch in 2015 has stuck with the trend he established in the two seasons prior. So why did its potency return? We'll get to that in a moment, but first, let's go into another pitch of his.

Kazmir has, literally since day one, had an intriguing slider:

Throughout his early years with the Rays, he relied on that pitch to retire batters, and it didn't disappoint. It resulted in a whiff 15.1% of the time he used it during 2007 and 2008, a higher rate than any other pitch in his arsenal. When its efficacy waned (he threw it past batters only 9.5% of the time in 2010), he unsurprisingly fanned fewer hitters, but he nonetheless still used it heavily. And through the first two years of his comeback, when his velocity had returned, it served him better than ever, as batters swung and missed at it 19.2% of the time.

With all of that said, Kazmir's slider never really impressed. Sure, it racked up the swinging strikes, but he couldn't turn it up to above-average velocity; even in his time with the Rays, it always hung around 83 MPH with movement to match. Two factors led to its success: its movement relative to his fastball, and his usage of it.

Observing Kazmir's pitching style for the Hardball Times (wow, those guys are machines), Josh Kalk noted that his slider excelled primarily because it contrasted so well with his fastball:

Kazmir’s fastball tails in so hard to left-handed batters and he throws it so often, he can fool hitters into this pattern. Then, when he throws a slider that begins out of the zone and doesn’t move much, the hitter is expecting it to bend back over the plate.

Looking at Kazmir's placement of the pitch in 2007 and 2008, we clearly see it diverging from his fastball:

The slider Kazmir threw to earn his first career punchout epitomized his slider usage overall. Four-seam up + slider down = duped batter.

Kalk went on to explain how Kazmir utilized the slider more heavily when he had two strikes on the hitter — a trend Kazmir continued for the first part of his renaissance:

Year(s)	Slider% (overall)	Slider% (2 strikes)
2007-2008	12.8%	22.5%
2013-2014	12.8%	19.6%

So the slider didn't have the traditional profile of a standout secondary pitch, but the manner in which Kazmir threw it made it better. In 2015, however, a problem has arisen: Its velocity has eerily declined to meltdown levels. Coming in at an average of 81.5 MPH thus far, it's unsurprisingly taken on a smaller role in Kazmir's repertoire:

Kazmir's replacement for the slider (and the reason why his four-seamer has done so well)? A new pitch, which he didn't even have before his resurgence: the cutter. 2013 and 2014 saw him use it sparingly (7.4% of all pitches), but 2015 has seen it take on a much more prominent role in his pitch mix, coming at hitters 22.2% of the time. In those instances, it's led to a whiff 11.9% of the time, a well above-average clip for the pitch type.

Kazmir doesn't throw Mariano Rivera's cutter. Its velocity, like that of the slider, clocks in at around the MLB average. Rather, it derives its clout from the spot it occupies — a familiar one for Kazmir:

Yes, the cutter has seamlessly replaced Kazmir's incapacitated slider by heading exactly where the slider used to go. In this way, Kazmir has found a new balance that works for him and has allowed him to shine anew.

His slider out and his cutter in, Kazmir has completed his evolution. But really, we don't have any way of knowing — in this crazy world of baseball, anything can happen. Maybe the slider, like the pitcher who once lived on it, will make a bold return; maybe the cutter will follow its path, and Kazmir will wash out for good. Who knows what the future holds?

. . .

All data courtesy of FanGraphs and Brooks Baseball, as of Wednesday, May 6th, 2015.

Ryan Romano is an editor for Beyond the Box Score. He also writes about the Orioles on Camden Depot and on Camden Chat that one time. Follow him on Twitter at @triple_r_ if you enjoy angry tweets about Maryland sports.