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Piniella: Zambrano to Bullpen

With Ted Lilly‘s return from the DL imminent, the Cubs had a decision to make. With two lefties already in the bullpen, the Cubs needed to move one of their right handed starters to the bullpen. There had been speculation abounding that Carlos Zambrano could possibly be the odd man out of the rotation, but few actually believed that manager Lou Piniella would expel him from the rotation over obvious choice Carlos Silva.

However, Piniella surprised us all this afternoon, announcing that Carlos Zambrano would indeed be moving to the pen. That leaves the Cubs rotation with Randy Wells, Ryan Dempster, Ted Lilly, Tom Gorzelanny, and Carlos Silva.

As I wrote earlier this month, I no longer consider Zambrano to be an elite pitcher. However, he is quite clearly one of the top-five starting pitchers in the Chicago Cubs’ staff. Zambrano’s FIP has typically been in the 4.00-4.50, but a good year last year suppressing the home run ball led to a 3.61 FIP, a 3.6 WAR, and his best season in three years. The projection systems saw Zambrano as a 3.90-4.10 FIP pitcher for 2010, and even despite his slow start, ZiPS’s updated projections expect a 3.80 FIP for the rest of the season.

Carlos Silva, on the other hand, has earned a starting rotation spot solely on the basis of two starts. Silva is 31 and coming off of two terrible seasons with the Mariners. None of the projection systems entering the season projected Silva to be better than a 4.64 FIP starter – above replacement level, but far worse than Zambrano, Dempster, or Wells, the other three right handed starters on the Cubs roster.

Not only that, but a move to the bullpen for Zambrano eliminates his greatest asset – his durability. Last season was the only year since 2003 in which Zambrano didn’t throw 200 innings, and he still made 30 starts and threw 188.2 innings. Zambrano’s been worth at least 2.8 wins per season in that time frame, and that’s in spite of his second-tier peripherals. Simply put, there aren’t many pitchers, regardless of their skill, who can throw that many innings year-in and year-out.

Silva, on the other hand, is fresh off an injury in 2009 and also missed time due to injury in 2008. He threw as many innings in 2008 and 2009 combined as Zambrano did in 2009 alone. Not only that, but even in his two excellent starts as a Cub, Silva’s fastball velocity is still 1.4 MPH lower than it was in his 3.3 WAR 2007 with Minnesota.

Carlos Zambrano is simply a better pitcher than Carlos Silva. Carlos Zambrano is simply a more durable pitcher than Carlos Silva. Instead of getting 180-200 innings out of one of his top pitchers, Lou Piniella is instead opting for about 40 to 50 innings from him and then 100 to 150 out of a pitcher who projected as average at best coming into the season. The Cubs’ chances at the division were low coming into the season. If Piniella’s rash and irrational decision stays in place, they become virtually nil.