Superman Hits the DL

A sour season for Matt Wieters owners got even more frustrating on Friday, as the switch-hitting would-be savior was placed on the DL (retroactive to July 10th) with a strained right hamstring. Wieters has been battling the bad hammy since tripping while rounding second base during a July 9th game against the Texas Rangers.

The fifth overall pick in the ’07 draft laid waste to minor league pitching in 2008 (a combined .355/.454/.600 between High-A and Double-A) and 2009 (.305/.387/.504 in Triple-A) before the O’s called him up last May. Wieters turned in a very impressive rookie season — while not reaching the hyperbolic expectations set by some, he hit .288/.340/.412 with a .331 wOBA in 385 plate appearances. League-average offense from 23-year-old backstop in the AL East is nothing to scoff at.

Wieters was supposed to take several steps forward in 2010, with both ZiPS (.282/.346/.427, .342 wOBA) and CHONE (.289/.355/.460, .356 wOBA) predicting improvement at the plate. Instead, the former Georgia Tech star has stung those who used a prime draft pick on him — Wieters holds a sluggish .245/.315/.357 line in 298 PA, with a .298 wOBA.

While Baseball America lauded the 6-5, 230 pound Wieters’ 30-homer potential, that pop has not yet been on display in the majors. He had a .124 ISO last season, and that mark has fallen slightly in 2010, to .112. For comparison, ZiPS projected a .145 ISO and CHONE had a .171 ISO.

Part of the problem is an increase in ground balls hit. Wieters hit grounders 41.9% in 2009, and that ground ball rate has climbed to 46.4% this year. It also doesn’t help that the quality of pitches that he’s swinging at has declined. Here are Wieters’ swing rates on pitches thrown outside of the strike zone (O-Swing) and within the zone (Z-Swing) in 2009 and 2010. I also included Wieters’ O-Swing and Z-Swing rates as a proportion of the MLB average:

Wieters is chasing a slightly higher percentage of pitches thrown off the plate (relative to the MLB average), but the big change is his swing rate on pitches over the plate. He’s taking more offerings thrown within the zone, which has contributed to his getting behind in the count more often. Wieters’ first pitch strike percentage was 53 last season, but it has climbed to 60.7% in 2010 (58-59% MLB average). According to StatCorner, Wieters took a pitch for a strike 29.5% of the time in ’09. This year, he’s taking a pitch for a strike 33.8% (31% MLB average).

Our Pitch Type Run Values suggest that Wieters is struggling on a per-pitch basis against fastballs — his runs/100 value against the heat is -0.49 this season, compared to +0.71 in 2009. According to Pitch F/X data from TexasLeaguers.com, Wieters swung at 45.8% of fastballs seen in ’09, and 41.3% in 2010. When Wieters got a fastball on the first pitch of an at-bat in 2009, his strike percentage was 54.4. This season, he’s got a 62.2 strike% when a pitcher throws him a fastball to begin an AB. It seems as though he’s having a hard time distinguishing balls from strikes against the gas.

Despite his struggles, Wieters is still one of the most valuable properties in the game. ZiPS has a .274/.343/.407 rest-of-season projection for him, and CHONE predicts a .276/.341/.431 line. Even if the power doesn’t manifest when he returns, Wieters isn’t a sub-.250 hitter. His .317 expected BABIP is 26 points higher than his actual .291 BABIP.

I can’t stress this enough — please, please do not trade this guy for fifty cents on the dollar right now. That goes ten-fold for keeper leagues — you’ll be kicking yourself later if you let the aggravation caused by Wieters’ tepid 2010 overshadow his superb track record and prospect pedigree.