Robertson said Wednesday afternoon that he was feeling a lot better and looser in that area. He felt tightness in it on his final pitches of the sixth inning, he said, but came out for the seventh hoping to loosen them up. He had trouble getting extension on his slider, which had been an effective out pitch for him all evening, then felt worse when he threw a first-pitch slider in the dirt to Matt Tolbert.
Had Robertson continued on and then left, he would've risked walking the ninth hitter in the Twins order ahead of leadoff man Carlos Gomez, with Joe Mauer and Justin Morneau looming a few batters later.
Robertson lasted 6 1/3 innings, allowing four runs on six hits with a walk and five strikeouts. It was the strongest of his three outings thus far this season and one of the better performances from a Tigers rotation that has largely struggled over the first two-plus weeks of the schedule.
It was the second time in five days that an injury knocked out a Tigers starter. Dontrelle Willis hyperextended his right knee when he slipped on the mound in Chicago during the first inning of Friday night's opener against the White Sox and left without retiring a batter. He is now on the 15-day disabled list; the Tigers called up Armando Galarraga to take his spot in the rotation for Wednesday's series opener against the Indians.
Jason Beck is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.