"Mechanically, he was kind of spinning off a little bit," Callaway said on Wednesday morning. "The last few outings, I don't think he's had a great feel for his mechanics. His changeup hasn't been very good, he's been kind of peeling off toward first base and leaving balls up, and it's kind of cost him. It's just a bad three starts mechanically."
Through 21 starts this season, McAllister is 7-9 with a 4.11 ERA and 90 strikeouts in 118 1/3 innings. Over his past three turns, the right-hander went 0-2 with an 8.78 ERA, allowing a .309 opponents' batting average in 13 1/3 innings. In his previous seven starts, McAllister went 3-2 with a 3.66 ERA and a .224 opponents' average across 39 1/3 innings.
Big innings have been mostly to blame.
In Tuesday's loss, McAllister allowed three runs on three hits without recording an out in the sixth inning against the Royals. In his previous start, on Sept. 4, it was another three-run, three-hit burst that sent McAllister to the showers. On Aug. 30, McAllister was tagged for four runs in a disastrous third inning against Detroit.
"Lately, it seems like it's four or five batters where he can't make an adjustment," Callaway said. "And it ends up hurting him. This is a big situation and he wants to compete so bad. Maybe he's just over-competing instead of just doing what makes him successful, just making pitches and keeping the ball down."
Jordan Bastian is a reporter for MLB.com. Read his blog, Major League Bastian, and follow him on Twitter @MLBastian. This story was not subject to the approval of Major League Baseball or its clubs.