Coming off his third consecutive strong start to begin the season (seven innings, five hits, one earned run on Sunday against the White Sox) and the first in which he actually allowed a -- gasp -- earned run, Greene is leading the Majors with a 0.39 ERA in 23 innings. While three starts isn't enough time to radically change the outlook of a pitcher, the right-handed starter has now been exceeding expectations since last July, when he pitched for the Yankees.
The Tigers acquired Greene from the Yanks in December in a three-team trade that also included the D-backs, and now it looks like Detroit general manager Dave Dombrowski pulled off one of the best deals of the offseason.
Originally an unheralded 15th-round pick in the 2009 First-Year Player Draft, the 26-year-old had an unremarkable Minor League career, with a 4.39 ERA in the Yankees' system. So Greene's 3.78 ERA and 9.3 strikeouts per nine in 78 2/3 innings in his 2014 debut looks like one of those rookie aberrations that, like a desert oasis, disappears upon closer inspection, even if his 3.73 fielding independent pitching (FIP) -- a stat that is supposed to measure a pitcher's performance on an ERA scale with "luck" factors removed -- suggests there wasn't much luck in his performance.
But there are still doubters. Baseball Prospectus' PECOTA, the most advanced and Ultron-like projection system out there, pegged Greene for a minus-1.1 wins above replacement player (WARP) this year. In fact, he would have to reach his 90th percentile projection just to be worth the slightest net positive for the Tigers at 0.6 WARP. With 0.4 WARP through three starts, Greene has nearly reached that.
What projection systems don't know is that Greene is a much different pitcher than when he was drafted. Before the 2013 season, the righty changed his mechanics and saw his walks and ERA cut in half. Which is the entire purpose of a Minor League development system -- to turn players from what they were to what they could be.
Even with a five-pitch mix and an OPS against just below that of pitchers like Max Scherzer and Jon Lester, Greene's reliance on a fastball and slider had some doomsayers predicting a move to the bullpen. It didn't help that lefties lit up the starter to the tune of .280/.363/.398 in 161 plate appearances in 2014. But after experimenting with a number of changeup grips last year, Greene finally settled on one shown to him by Yanks pitching coach Larry Rothschild. So far, the decision seems to be paying off.
In his three starts, Greene has thrown the change 12 percent of the time, four times the amount he tossed it last season, getting swings on 12 of 20 that he's thrown. Again, small sample size, but already lefties are just 3-for-24 against him with one double.
There are a few caveats, though: Greene has faced struggling lineups in the Twins, Pirates and White Sox, who rank 26th, 18th and 24th in the Majors in runs. And he's also seen his strikeouts nosedive to just 4.3 per nine innings, 14th worst in MLB, while putting up an unsustainable .188 batting average on balls in play.
In other words, some regression is in store, and Greene certainly won't finish the season with a 0.39 ERA. But for the 15th-round selection with stuff that Brandon McCarthy called "stupid electric" on Twitter, it's time to believe.
Michael Clair is a reporter for MLB.com. Follow him on Twitter at @clairbearattack. This story was not subject to the approval of Major League Baseball or its clubs.