Ubaldo Jimenez: What Went Wrong?

Ubaldo Jimenez was by far the most dominant pitcher in the first half of the 2010 season.  But after the All Star break, his numbers started to decline.  For the first half of the season, Jimenez went 16-2 with a 2.20 ERA; batters hit .198/.280/.302 against him.  But in the second half, he managed only 6 wins in 15 starts, with a 3.80 ERA.

One noticeable change in Ubaldo's second half was his fastball location.  Take a look at the difference in how he spots the pitch in the second half:

Ubaldo Jimenez Fastballs (Click to enlarge)

Jimenez began to leave his fastball up more as the season progressed. However, this only accounted for a .033 point jump in batters' wOBA versus the pitch. In fact, Jimenez actually saw an increase in his strike out rate on fastballs. While his second half decline was fairly stark, the fastball doesn't seem to be at the root of his problems.

In a post to follow, we'll take a closer look at some of his other pitches down the stretch.

Colorado Rockies' Lucky CarGo

Over at Purple Row, Bryan Kilpatrick recently wrote about expectations for Colorado Rockies outfielder Carlos Gonzalez in 2011.  CarGo's first full season in the majors was a tremendous success as he hit .336/.376/.598 and finished in the top 10 in wOBA.  But hitting at Coors probably inflated his overall numbers as his home/road splits indicate.  Kilpatrick notes that CarGo was still above average when compared to how the rest of the league performed away from home.

But what really interested me was Cargo's .384 BABIP last season (top 1% in the majors), indicating he had a fair amount of luck at the plate.  Kilpatrick argues that Gonzalez has "the hit tools necessary to avoid a complete statistical plunge due to BABIP regression." 

I took a look at his pitch splits and found that CarGo had a .417 BABIP versus fastballs, the highest in all of baseball last season.

2010 Top 10 BABIP vs. Fastballs

On average, half the pitches a batter will see in a given season will be fastballs.  I'd argue that CarGo's very high BABIP on fastballs is likely due for serious regression; however, he also managed a 26.6 LD% vs. fastballs last season, and his overall LD% has been climbing every year.  If CarGO continues to square up fastballs as he's been doing, his overall line might not take such a hit when(if?) that BABIP drops.