Extra Mustard By Baseball Prospectus

WITH ADAMWAINWRIGHT on the verge of bullpen stardom (11 strikeouts, no runs allowed inseven innings during the postseason), should the Cardinals continue to use himas a reliever or turn him back into a starter? While Wainwright's numbers thisseason improved considerably from 2005, when he was used exclusively as astarter, that should not come as a surprise. Baseball Prospectus researchindicates that the typical pitcher can expect a 25% reduction in his ERA if hemoves from the rotation to the pen; Wainwright saw his ERA drop from 4.40 in'05 (in Triple A, no less) to 3.12 this season.

Wainwright is notthe only young, recently converted closer whose potential value as a starterhas been hotly debated in recent months. In September the Red Sox announcedthat Jonathan Papelbon (35 saves, 0.92 ERA in '06--his first season as afull-time closer) would rejoin the rotation next season. Earlier this year, onBaseballProspectus.com, I argued that the Red Sox should not take Papelbon outof the closer role and identified two characteristics of pitchers who tend todo better in the bullpen: They are occasionally wild, due in part to imperfectmechanics, and they don't give up a lot of home runs. Like other successfulstarter-to-reliever converts such as Tom Gordon and J.J. Putz, Papelbon hasthose characteristics.

But the25-year-old Wainwright is not that sort of pitcher. His command has always beenhis biggest strength, which suggests that his mechanics are stable enough tohandle longer outings. And his reliance on the curveball--a pitch that can behit a long way when it hangs in the strike zone--has led to periodic problemswith the home run ball throughout his professional career. Wainwright shouldcontinue to serve St. Louis well as a closer, but he might be even morevaluable to the team as a starter, a role in which his numbers and repertoireresemble those of the late Darryl Kile.

PHOTO

CHUCK SOLOMON

LEARNINGCURVE

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