C.J. Wilson the Starter

After enjoying a career year pitching out of the ‘pen for the Rangers in 2009, C.J. Wilson was shifted to the starting rotation this past spring. Prior to April 8th, 2010, the 29-year-old hadn’t taken a big league mound as a starter since August 18th of 2005. Strictly a reliever from 2006-2009, Wilson whiffed 8.94 batters per nine innings, walked 4.26 per nine and had a 51.1% ground ball rate. In March, Matt Klaassen theorized about Wilson’s value taking the ball every fifth day instead of pitching in short bursts. The whole article is well worth a read, but here are a couple tidbits:

How good would Wilson be as a starter? CHONE projects him to have a 3.70 FIP in 2010, and ZiPS projects him for 4.17 — an average of about 3.94. Both of those projections are based on Wilson’s performances as a reliever, and as a general rule one estimates that a reliever will be one run per 9 innings pitched worse as a starter. A 4.94 FIP isn’t replacement level, but even in Texas’ hitter-friendly home park, that’s nothing to get excited about other than as a stopgap or back-of-the-rotation type.

However, Klaassen also noted Wilson’s increased ground ball rate in 2009, as well his improved performance against right-handed pitching:

I don’t have a firm conclusion. At first glance, we wouldn’t expect Wilson, a capable reliever, to be that effective as a starter. However, if the new cutter has not only helped his platoon issue but has expanded his repertoire so that he can to get through the order more than once (and perhaps get even more groundballs), then — provided he can handle a starter’s workload over a full season — the Rangers might have something more than just a stopgap starter on their hands.

So far, it looks like Wilson has blown by that modest projection — he holds a 3.35 ERA in 113 innings pitched. But, if you look a little closer, you’ll find some cracks in his seemingly stellar first half. In truth, Wilson has pitched much closer to the level Klaassen forecasted than the lefty’s ERA would indicate.

Navigating lineups multiple times, Wilson’s got 6.53 K/9, 4.38 BB/9 and a 49.5% ground ball rate. As those ratios suggest, Wilson isn’t whiffing a lot of batters or displaying particularly sharp control. Texas’ fifth-rounder in the 2001 draft has a 6.6% swinging strike rate (8.4% MLB average this season), and his contact rate is 83.7% (81% MLB average). Wilson’s getting into hitter’s counts more often that you’d like, throwing first pitch strikes 53.6% (58% MLB average), and he has been about average in terms of putting his offerings over the plate (47.3 Zone%). On pitches out of the zone, Wilson’s garnering swings just 23.4% of the time (28.6% MLB average).

As a starter, Wilson’s using his fastball (down about three ticks in velocity) less than half of the time. He’s going to a high-80’s cutter about 19 percent of the time, a low-80’s slider 12 percent, a low-80’s changeup 13 percent and a mid-70’s curveball on roughly eight percent of his pitches. That cornucopia of pitches has worked wonders against same-handed hitters, but Wilson’s underlying performance against righty hitters leaves much to be desired:

Clearly, Wilson has been fortunate in not yet surrendering a homer to a lefty and in having a microscopic BABIP against them. But he has been pretty effective against LHBs overall. It’s a different story when an opposite-handed batter steps to the plate — Wilson’s often losing the zone against RHBs.

Not that a half-season’s worth of starts should serve as definitive judgment on Wilson’s abilities as a starter, but his peripherals are rather close to what Klaassen predicted. Wilson’s xFIP is nearly 1.4 runs higher than his actual ERA, at 4.71. He has benefitted from a .250 BABIP, seventh-lowest among qualified MLB starters, and he has served up homers on fly balls hit against him just 6.1% of the time. That’s one of the twenty lowest rates among big league starters, and is well below the typical 11% range for pitchers.

If Wilson continues to strike out and walk opponents at a similar clip in the second half, his ERA will almost assuredly rise by a significant margin. There’s also the workload issue to consider — Wilson’s previous career high in innings pitched is 136, and that was at High-A and Double-A back in 2002. Perhaps he’ll handle the increase just fine, but he does have a history of arm ailments (Tommy John in 2003, a biceps strain in 2006, elbow soreness and subsequent surgery to remove a bone spur in 2008, according to the Baseball Injury tool). The point is, we just don’t know.

Given his mild K and walk totals and his entering unchartered territory in terms of innings pitched, Wilson’s a good sell-high candidate. If you can convince an owner that Wilson’s an upper-echelon starter instead of a decent rotation arm with a good deal of risk, now’s the time to make a deal.