Manager Bruce Bochy said he pulled Lincecum because he had thrown 90 pitches. Lincecum said he has a hyperextended thumb in his left, non-pitching hand.
"Nothing bad," Lincecum said. "Just rattled a little bit, but nothing bad."
With two outs and Cowgill at second, Lincecum threw a wild pitch to Jemile Weeks. Catcher Buster Posey couldn't find the ball quickly, which allowed Cowgill time to race home. Posey tossed the ball to Lincecum, who got down low to make the tag. As Cowgill slid, his helmet flew off and it appeared to hit Lincecum in the head as the pitcher absorbed the collision. Lincecum appeared to apply the tag in time, but the ball flew out of his glove.
Cowgill was safe, and the collision sent Lincecum backward but he immediately stood up. After an official delay in which a trainer visited Lincecum, he walked Weeks and got Cliff Pennington to pop out and end the inning, with the A's having scored four runs in the frame for a 4-2 lead.
In the bottom of the inning, Nate Schierholtz pinch-hit for Lincecum. Right-hander reliever Shane Loux pitched the fifth inning.
Willie Bans is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.