The Twins have all but guaranteed that the top three starters to begin the season are Ervin Santana, Phil Hughes, and Kyle Gibson. Three viable candidates remain for the final two rotation spots to start the season. Each has factors in their favor and each has deficiencies that might put him in the bullpen or the minors.
Tommy Milone-Milone finished 2015 in the rotation after earlier being sent to the minors and also missing time with minor arm issues. He finished the season with a 9-5 record and a 3.92 ERA. Milone would be classified as a young veteran-he's 29 and has logged 619 innings in just under four years of service time. He is a lefty, the only southpaw competing for a spot in the rotation. Tommy is not known as overpowering, featuring a <90 mph fastball and no dominating pitches. Milone can't be classified as durable, exceeding 160 innings only once in his career and he has only two complete games, the last in 2013. Milone fanned 6.4 per 9 innings in 2015, in line with his lifetime rate of 6.5 per nine. Milone has always achieved better results than his peripherals, compiling a lifetime 3.97 ERA despite a lifetime 4.23 ERA and having a better ERA than FIP every year since his cup of coffee with Washington in 2011.
Tyler Duffey-Duffey also finished 2015 in the rotation after a nice run in Rochester. He was very impressive in his debut season for the Twins, going 5-1 with a 3.10 ERA, fanning 8.2 per nine innings. Duffey features a couple of different curve balls that mystified hitters in his rather brief stint with the Twins last year. Duffey is 25 and was a relief pitcher in college. There is a possibility that hitters will catch up with Duffey in a full season, especially since he doesn't throw terribly hard. Duffey has options remaining and could be sent to Rochester without risk of being lost to another team.
Ricky Nolasco-No pitcher the Twins have had since Ron Davis has done more to be poorly regarded by the home fans than Ricky Nolasco. He came to the Twins with a reputation of being a solid mid-rotation starter who would log plenty of innings and he came with a big paycheck-over $12M per year. In his first two years with the club, he hasn't earned his paycheck, not even close. He's only pitched 196 innings and hasn't been effective-an 11-14 log with a bloated 5.64 ERA. Nolasco has whiffed 6.9 per nine with the Twins, in line with his 7.3 per nine average. Ricky has two years remaining on his big contract and is 33 years old. Significantly, in Nolasco's career, his achievements don't come close to his peripherals. He has a lifetime 3.81 FIP, but a lifetime 4.54 ERA. As a Twin, the difference is even more dramatic (4.15 FIP vs 5.64 ERA).
IMHO, at some point FIP loses it's luster as a predictor of performance and I think that is the case for both Nolasco and Milone. Milone will most likely exceed his peripherals and Nolasco will not. Milone has performed better more recently, is younger and is a lefty. In my book, he wins out for sure over Nolasco. Milone should be and probably will be the #4 starter.
Nolasco vs. Duffey is a bit tougher to call. Duffery ML experience is limited, he does have both bullpen experience and options remaining. Nolasco has a decent history plus that contract. Both Duffey and Nolasco have had a bad outing in Ft. Myers, while pitching better in their other appearances. I would predict that Nolasco is given a spot in the rotation and that Duffey is either optioned or sent to Rochester. I think Duffey should get that spot with Nolasco in the bullpen as a starter-in-waiting.