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What To Do About Roy Oswalt

We’re deep in the heart of Roy Oswalt Watch 2012, which is not quite a hullabaloo but is slowly ratcheting up the volume and frequency. Now the rumor is that he’ll go to the Rangers. Should he picked up in all leagues right now?

First, the obvious answer is that the deeper your league, the more likely it will make sense to pick him up. Before we go negative on Oswalt, he’s only 34 years old and he’s been very useful the last two years in the league. He’ll still throw over 90 and he’ll still have his slider and curveball, and he’ll still show great control in all likelihood. That takes a pitcher pretty far in deep leagues.

But how about your typical twelve-teamer? Then it gets a little murky, especially if he ends up in Texas.

Pick a stat, any stat, and Oswalt is in decline there. Velocity — down to 91.4 MPH from 93.7 in 2002. Strikeout rate — down to 6.02 per nine last year from an average just over seven. Swinging strikes — down to 8.0% and significantly below average for the second time in his career. Ground-ball rate — down to 45.1% from an average of 47.3%. FanGraphs provides a fan-tastic graph for the one stat whose decline is the most obvious:

One thing you’ll notice is that Oswalt’s xFIP (3.95) and SIERA (4.04) were worse than his 3.44 FIP in 2011. Both normalize home run rates to some degree, and Oswalt’s 6.3% home runs per fly ball last year was the lowest of his career. That number normalizes to 9-10% every year across baseball, and there’s no research that indicates that a pitcher can control it. His career number is 8.8%. He could expect an ERA much closer to four based on that statistic alone.

If the latest rumor is true, and Oswalt is headed for Texas, the damage could be worse. Our park factors have the Rangers’ park augmenting home runs by 9% (11% for lefties, 7% for righties). That should help push the home-run-per-fly-ball needle back to league average.

Not only will the park be harder on the pitcher, but so will the league. Various studies have found that the move from the National League to the American League can cost a pitcher half a strikeout per nine, or as much as 10% in ERA+. Oswalt had a 96 ERA+ last year and was exactly at league average in 2009. His strikeout rate was a full strikeout per nine below league average last year. Neither of those numbers can afford a healthy ding.

Back to our original caveat, those desperate for pitching in leagues of depth can reach for the free agent. He is certainly a skilled pitcher and will have some great matchups along the way. But for those of you in standard mixed leagues, Oswalt will have to ride your bench with the Yankees and Red Sox come to Texas — don’t stash him now if you can’t sit him much, or if your league is stream-friendly.