Chris Tillman started the season in the starting rotation, and actually managed to hang around in the majors until the end of May. At that point, with a 4.69 ERA in 10 starts, Tillman was sent down to Triple-A. That's where he spent most of the season, before being called by up for a short stretch at the end of July (three starts - one good, two bad) and then sent back down to end the year. I had projected 120 innings of 5.00 ERA ball from Tillman, but he didn't manage to get there on either count.
In the minors, Tillman pitched 76.1 innings of 5.19 ERA ball. His old minor league strike-out ways look behind him (6.4 K/9) and he didn't even manage to keep the walks down (4.4 BB/9). He also gave up 17 home runs - an awful 2 HR/9. Given that level of production, it's actually a little amazing that he ended up getting called back up as opposed to sent down further.
In the majors, Tillman pitched 62 innings with a 5.52 ERA, 3.99 FIP, and 4.83 xFIP. His strike-out rate of 6.7 K/9 was actually easily a career high (if still below average) while his control looked more like 2009 and (the worse) 2010 with a 3.6 BB/9. A 1.8 K/BB ratio certainly isn't good, but it can be manageable. Unfortunately for his ERA, Tillman had a .348 BABIP against (which seems like largely bad luck - his line-drive rate wasn't too high and he did manage to induce a fair number of pop-ups). And unfortunately for his xFIP, he continued being an extreme flyball pitcher. That only 5-6% of his flyballs ended up leaving the yard - leading to a 0.7 HR/9 - is what led to the below-4 FIP and, thus, his 1 fWAR (amazingly, the 4th highest for a starter on the team).
Stuff-wise, the lowered velocities continued; his average fastball came in at just 89 mph (90 mph last year, 92 mph the year before). There were a couple starts in his second stint with Baltimore where he was more 91-92 (with an 11-2 strike-out to walk ratio to boot), but then in the third game of the set it was back down to 89-90. A twinkle of hope, and then... bleh. Interestingly, calls to develop more pitches don't seem to be helping either. Tillman not only had that (straight, slow) fastball, the (now straighter) change-up, and the big curve (which got left up in the zone a fair bit), but also an occasional cutter (which generated a solid 24% whiff rate) and a new slider. So that's five pitches - none of which seem that great at this point (the curve could be if he could get ahead in the count more and had better control of it).
Interesting note; for his career, Tillman has actually struck out left-handed batters at a much higher rate (6.6 K/9) than right-handed batters (4.9 K/9) and given up homers to them less often (1.1 HR/9 to 1.8 HR/9), though also walking them more (4.7 BB/9 to 3.2 BB/9). That's given him a reverse platoon split; 4.93 FIP and 4.93 xFIP versus lefties, and 5.75 FIP and 5.09 xFIP versus righties. Tillman's breaking-balls have gotten more whiffs against opposite-handed batters while his change-up has gotten more whiffs same-handed batters (fastballs were about the same) - not what one would usually expect. Maybe it's because the lefties see the change more than twice as often? Not sure, but it's the first time I think I've noticed the differences.
Still just 23 years old, it's not necessarily time to completely write Chris Tillman off. There are still sparks of talent every now and again - even if it's just for one game, or one inning - but to become even an average major league pitcher he'll need to either (1) walk many fewer batters and hope to limit home runs, (2) figure out a way to mix his pitches to maximize how many bats he can miss to up his strike-out rate, or (3) figure out where his stuff went and get it back. Seems like the odds of all three happening (which would be needed to get Tillman to what his perceived ceiling was when the O's acquired him) are extremely small; I'd gladly take just one (though given the O's player development, I'm not holding my breath).