Jered Weaver

When an already-good pitcher gets better, it’s time to ask why. As is often the case, we can start with a few bits of news from the colder months of the year.

Jered Weaver spent significant time on his two-seam fastball during 2010 Spring Training. It started with a version Joel Pineiro taught him in February, but he ended up going back to the grip he had been using over the past two seasons. Actually, you can find reference to Weaver’s two-seamer back to at least 2006 in Google News, but he started using it regularly in September 2008.

Jered Weaver pitch selections

Left pane: selections by season; right pane: upper region is LHH and RHH for 2007-2008, lower region is is 2009-2010

Unlike his older brother Jeff Weaver, the younger Weaver comes right over the top*. This gives his fastball an almost cutting motion, in addition to good “rise.” That’s not always the best thing against left-handed batters, so Jered’s two-seamer gives him a fastball that will run away from the lefties. Run being the operative word, as that over-hand delivery turns sink into run with a two-seamer.

*Usually. Jared also will drop down some times, but he seems to be doing it less

That deserved more than an asterisk.

Jered Weaver release points by season, home games

shown from catcher’s view

You can find the key for those pitch colors in the following graphs, which will introduce you to Weaver’s full arsenal. But you can see a lack of low-angle pitches in 2010.

Jered Weaver pitch graphs

Top left: spin deflection relative to ball under the influence of gravity alone, catcher’s view; top right: pitch speed by spin orientation; bottom: flight paths from bird’s-eye view, first-base view and catcher’s view (inset)

You could argue the slider and the curveball are the same pitch thrown different speeds.

Pitch metrics

Boiling it down toward the bottom line, Weaver has been a quality pitcher over his career but is having a breakthrough season—so far.

What’s your favorite pitching stat? I use a few, ranging from my own rv100a and rv100e (linear weights turned into an ERA-like number, “a” uses play-by-play outcomes, “e” uses league-average outcomes by batted ball type, both are based on the ball/strike count and run expectancy changes) to the found-at-fangraphs FIP, xFIP and tERA.

No matter how you slice it, this has been a good year for Weaver. Given his increased reliance on a two-seam fastball, let’s look at a few things pitch-by-pitch. rv100e and rv100a are shown below, along with whiff rate (misses per swing), ball to called-strike ratio, groundball rate and pop-up rate.

For each pitch (and overall), we’ve included updated benchmarks for comparison (MLB2010) along with Weaver’s three-year totals (JW07-10).

Overall

Weaver was, by these numbers, in the top 30 or 40 of MLB starters in 2008 and 2009. With limited PITCHf/x data available for 2007, I can only say “about the same.” For 2010, he’s beating the world. It’s important to note, the best full-season rv100e I have is owned by John Smoltz**, from 2007. Tim Lincecum (2009) and CC Sabathia (2008) have the only other sub-3.00 seasons. Weaver’s rv100a, which is trick-able by good luck on balls in play, would be ranked 19th for seasons of 1500 or more pitches (in PITCHf/x), tied with Josh Johnson’s 2009 campaign. Four pitchers have gone below 2.00 (Chris Carpenter, Lincecum, Justin Duchscherer and Chris Young**).

**2007 does not have complete PITCHf/x data

In case you’re wondering, Weaver leads the majors in rv100e this season (minimum 1000 pitches). He’s trailed by Cliff Lee, Adam Wainwright, Mat Latos and Ryan Dempster (all < 3.00). In rv100a Weaver ranks 20th, with Mr. Lee leading Matt Cain, Johnson, Wainwright and Latos with sub-2.00 numbers.

Two-seam fastball

I typically refer to two-seam fastballs as sinkers. That is not the case here. You can just about disregard 2007 and 2008, when Weaver threw just 30 and 98 two-seamers, respectively. If you look back at the release point charts, you may wonder how many were just four-seamers launched from a lower arm slot. Whatever the case, getting a moving fastball is beneficial for Weaver’s long-term success. His fastball really doesn’t cut so much as it just goes straight. He’s not Mariano Rivera, Jenrry Mejia or even Joakim Soria. While straight, Weaver’s height and release point produce a downward plane which often works in favor of a change-up. And, apparently, a two-seam fastball prone to pop-ups.

So far, Weaver’s two-seamer has been more effective, but I’d say the jury is out on a grade. It’s probably not good to compare it to other two-seam fastballs, unless you cherry-pick them from the Latoses of the world.

Change-up

OK, so maybe that downward plane deception is working here. Weaver has a tremendously effective change-up. What more could I add to these results?

Four-seam fastball

A fairly average pitch is now a plus-plus pitch. Jered doesn’t throw a ton of strikes with his fastball, but no one seems to be hitting it.

Curveball

Looks like an even-year pitch, doesn’t it? Up year or down year, it’s a plus pitch. Note the upward trend in ground ball rate. Here’s another upward trend … slider whiffs.

Slider

Hello, Brad Lidge territory. Also extend a greeting to declining groundball rates. Put it together, you have an average pitch.

Summing up

Weaver looks to be at his best in 2010, clicking with all of his pitches. Everything is at least average—which is better than average to begin with, he’s a starter, not a reliever, and he’s in the American League. He probably can’t keep it up, but I wouldn’t expect him to regress too far. First, there’s no sign of extreme luck in batted balls, judging by the small gap between rv100a and rv100e. Second, young pitchers can improve. Weaver seems to have developed a good two-seamer to complement his already effective fastball/change-up/curveball combination. His slider is nothing to scoff at, so we’re talking about someone with five quality pitches. Guys like that win Cy Youngs.

References & Resources
PITCHf/x data from MLBAM and Sportvision. Batted ball data from MLBAM. Pitch classifications, linear weights (rvERA) and other pitch metrics by the author. All other statistics from Fangraphs.