Lincecum struck out five, supporting his observation that his "stuff was moving around pretty well." But he yielded Yoenis Cespedes' two-run homer in the first inning on a hanging slider, issued a pair of walks to help the A's score in the third inning and yielded opposing pitcher Tommy Milone's fourth-inning single to prompt his removal from the game.
"I had some good moments and some pretty bad ones," said Lincecum, who surrendered a Major League-high 28 first-inning runs and walked a career-high 4.4 batters per nine innings last year.
Lincecum threw 80 pitches, which was good because it increased his stamina.
"I didn't feel like I was fatiguing," he said.
He struggled to repeat his pitching mechanics, which was bad because he couldn't locate his deliveries where he wanted.
"I'm letting batters get away. I'm not finishing guys off," he said.
Lincecum believed that consistency remained within reach.
"Confidence-wise, I know I can still get outs," he said. "It's not a matter of worrying about guys getting hits or being fearful of that. If I just make my pitches, I'll be good."
Buster Posey, who caught Lincecum for the second straight game, expressed support.
"Timmy's working his tail off," Posey said. "He's working between each start. He's in the weight room all the time. He knows what it's going to take. Just keep on grinding."
Chris Haft is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.