As players age, certain elements of their on field performance begin to decline. Speed, velocity on a pitcher's fastball, and arm strength and mobility for outfielders are just a few examples. For a hitter like Carlos Lee, the ability to hit for power has proven to be a huge part of his game over his career. Since becoming a full time outfielder with the White Sox in 2000, Lee has never failed to hit fewer than 24 home runs in a season.
This season though, Carlos hasn't been as potent at hitting the long ball. His 13 home runs at the All Star break coincide with a relatively low .485 SLG%, and a near career low ISO of .177. The isolated slugging percentage drop off hurts the most, as the Astros are struggling to hit for extra bases as a team. As I wrote earlier this summer, ISO is the offensive statistic that correlates most strongly with winning baseball.
Should we have seen this coming? Can Carlos Improve?
Here is what two projection systems had for Carlos this season, in terms of SLG%:
| Projector | SLG% |
| PECOTA | .505 |
| CHONE | .522 |
Even the notoriously conservative PECOTA had him slugging higher than his current .485. Let's see what ZIPS has him projected to do for the remainder of 2009:
| SLG% | ISO | HR | 2B |
| .497 | .192 | 25 | 32 |
He's supposed to improve, but will still be below his career averages in both SLG% and ISO. Some interesting peripheral statistics to take note of: Lee's HR/FB% is at a stout 10.4%, but his FB% is down from years past. This means that for the first time in his career, his GB/FB rate is above one. This may just be a one year decline in his power stats, but at 33, Carlos is most likely entering the decline years of his career. It's not so much that he's not hitting home runs as he has in years past- it's his low ISO. In order to justify his contract, and for the Astros to stay in the hunt, his best bet lie in upping his 2B totals to the high 30s or 40s.
Believe it or not, Carlos has outperformed his salary so far in his tenure as an Astro. He'll be hardpressed to do so this season and in future seasons as well, but adding to his double totals would help mask the fact that his best home run days may be behind him.