Where'd Puma's power go?

In Yankeeist's August Monthly Wrap-Up I noted that the Yankees' offensive fortunes would improve with the return of a healthy and effective Alex Rodriguez and Lance Berkman. Thus far Alex has more than lived up to his end of the bargain, slaughtering his ZiPS RoS projection on September 1 of .272/.364/.489 to the tune of .356/.423/.667. Berkman was projected to go .262/.380/.464 with four home runs in September, and thus far he's hit .364/.451/.409 with no home runs.

I don't mean to ride Berkman too hard, especially since he's clearly been one of the Yankees' better hitters during the month of September. However, after watching him hit for nearly 100 plate appearances as a Yankee, half of which have come in September, I can't help but wonder where his power's gone.

Part of the reason is due to his batted ball profile -- as a Yankee he's hitting line drives 15.5% of the time (compared to 19.7% for his career), ground balls 52.1% of the time (42.4% career) and fly balls 32.4% of the time (37.9% career).

While it's tough to extract too much from the pitching data given such small samples, he's also seen less fastballs and sliders than he'd been seeing as an Astro, and more curveballs (in fact quite a bit more -- 9.0% in the NL to 10.1% in the AL) and changeups. There may be something to the curveball data -- as an Astro his bat was worth 3.3 runs above average against the curve, while as a Yankee he's at -0.8. Again, super small sample size caveats are in full effect here, but it's still interesting to note.

While he's still taking his share of walks, Lance has also not been as patient as he was as an Astro, as his walk rate is down to 12.6% from 16.8% (15.5% career) and he's also having quicker at-bats, seeing 3.62 pitches per plate appearance as a Yankee compared to 4.14 as an Astro.

Basically it appears that Lance isn't waiting for his pitch and is allowing himself to get beat by an array of off-speed stuff. The latter component of that sentence makes it clear why Brian Cashman wanted to obtain him, as he further underscores the Yankees' most glaring weakness.

Kidding aside, Puma's going to have to be more selective to get that SLG up. There are only 13 regular season games left, so I wouldn't expect a barrage of doubles and home runs, but if he can start lofting the ball in the air more hopefully we'll at least finally see his first home run in pintsripes. The Yankees need his bat to be even more potent if the team expects to make a deep run into October.