San Francisco Giants right-hander Tim Lincecum is set to undergo treatment and further evaluation on his tight back once the team returns to AT&T Park.

The team was preparing to leave Kansas City before an off-day World Series workout Thursday in the Bay Area. Athletic trainer Dave Groeschner says in a text message that "he is doing OK" and Lincecum will be checked out further.

The two-time NL Cy Young Award winner was walked off the field by Groeschner during the eighth inning of San Francisco's 7-2 loss in Game 2 when his lower back tightened up on him. He hadn't pitched since Sept. 28, not called upon out of the bullpen during the NL Division Series against Atlanta or the NLCS versus St. Louis.