Five talented young pitchers are attempting to enter the rotation this spring after making their first marks in the majors in relief: Neftali Feliz, Daniel Bard, Chris Sale, Aroldis Chapman and Aaron Crow. They have all excelled in the bullpen, but they don't have a single big league start among them. However, they do have starting experience, as all but Sale, who started in college, have pitched out of the rotation in the minor leagues. Chapman also started in Cuba before signing with the Cincinnati Reds in 2010.
If those pitchers have all bid their final farewells to the bullpen, sabermetricians will celebrate because statistics suggest that starters are the most essential members of the pitching staff. The best reliever in baseball last season (according to wins above replacement player), Craig Kimbrel of the Atlanta Braves, had a 2.2 WARP. In comparison, there were 70 pitchers who made at least 30 starts in 2011, and they had an average 2.1 WARP, primarily because of all the extra innings they threw. Bottom line: A decent starter is much more valuable than an excellent reliever.