Tim Lincecum was forced to leave Wednesday's Game 2 after retiring five batters. (USATSI)
Tim Lincecum was forced to leave Wednesday's Game 2 after retiring five batters. (USATSI)

KANSAS CITY -- Tim Lincecum, the Giants' iconic starter-turned-reliever who came out of Game 2 after feeling sudden tightness, will be getting an MRI on Thursday on his lower back/left side region, according to sources connected to the team.

No one with the Giants has said yet whether Lincecum will remain active, but the MRI could tell the tale.

Lincecum, the two-time Cy Young winner who struggled in the second half this season after a big start, felt the tightness after throwing a pitch in the eighth inning. He retired all five batters he faced, and looked like the dynamic reliever he was in the 2012 World Series before having to leave the game.

Lincecum felt frustration after the game, saying about his outing following a long layoff, "You finally get out there, and you hurt yourself on one [single] pitch. It's just bad luck I guess."

Lincecum has been dealing with some lower-back pain during the year, which was up and down for him, and there has been suggestion it could be into the hip area -- though Lincecum said he would have to ask a doctor whether it could be hip related.

Giants manager Bruce Bochy expressed hope after Wednesday's game, saying, "We think he'll be fine."

Lincecum could be replaced on the roster if he can't pitch, and the San Jose Mercury News identified George Kontos, Juan Gutierrez and Erik Cordier as potential candidates to replace Lincecum.

Bochy still had his mind on Lincecum, though. "We're going to need help in the sixth, seventh inning," he said. "I like the way he threw the ball."