Warren hasn't put it all together yet, but he consistently misses bats while limiting the walks enough to keep the dream of starting alive. He had a 10.32 ERA and 1.90 WHIP in 22.2 innings last year in his first taste of the majors, yet Warren's 17.3 K-BB% was better than Luis Gil's 14.8 K-BB% and in the same ballpark as Nestor Cortes (17.3 K-BB%), Clarke Schmidt (17.8 K-BB%) and Gerrit Cole (17.9 K-BB%). Warren's best offering by far is his low-80s sweeper, and that fastball/sweeper combo allowed him to log a 28.6 K-BB% against righties, but he was completely ineffective against lefties (1.9 K-BB%, 2.30 WHIP), and he'll need to improve either his changeup (12% usage) or cutter (4% usage) to successfully navigate a big-league lineup multiple times. Warren should return to Triple-A, but he could make double-digit starts in the majors as a fill-in option with a dash of breakout potential and a good reason to watch him in the spring (looking to see how he does against left-handed hitters). Read Past Outlooks