Thursday, June 25, 2009

Blackburn, K-rates and a bad loss

The Twins took a tough loss Wednesday night. It was the kind of game that (speaking purely subjectively, without a trace of objective analysis behind it) good teams win because good teams don't beat themselves by heaving balls from outfield warning track to backstop and back to the warning track.

(Having raised the issue, I wonder how many times a pennant winner has lost a game by committing a pair of two-out throwing errors in the bottom of the eighth.)

Nick Blackburn was in the middle of the disaster, and Blackburn is, by conventional standards, having a fine season: 6-3, 3.11 ERA (eighth in the American League) leading the team in innings pitched (almost 17 more than Kevin Slowey), 10 quality starts in 15 starts).

He's not an ace. He's a decent pitcher pitching well, not a legitimate Cy Young contender or even an All-Star. And he's not a particularly good bet to keep this up.

Why? His strikeout rate — 41 Ks in 101.3 IP, 3.44 per nine innings is year — is low. Lower, even, than his career rate, 4.31. It is incredibly difficult for any pitcher, but particularly a right-hander, to sustain success with K-rates that low.

See Joe Mays. Or Carlos Silva. Or the Twins-era Scott Erickson. The Twins have, obviously, a long history of similar pitchers — guys who are supposed to rely on their sinkers (also known as two-seam fastballs) but don't really get that many ground balls.

They'll have a good year or two, then recede into the mediocrity their inability to miss bats dictates. (Or, as Erickson did in Baltimore, they'll find a way to boost their strikeouts).

This is why Scott Baker and Kevin Slowey are better than Blackburn. Baker is 13th in the AL in K/9 this season (7.6); Slowey is 16th (7.1). This is also why Francisco Liriano (eighth, 8.1) cannot be given up on. Blackburn? Last among the 46 qualifiers in the American League.

This has been a blind spot for the Twins in the past. K-rates are a better predictor than ERA. But the Twins have a history of hobbling themselves with long-term deals for low-strikeout pitchers. As long as the Twins recognize Blackburn's limitations, fine. If they take a good 2009 season as evidence that they should build the rotation around him, it's a problem.

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