Lincecum showing improvement

SAN FRANCISCO -- The Giants aren't going to rush Tim Lincecum back into the lineup even though their staff ace has shown improvement after back spasms forced him to miss his start Tuesday night against the San Diego Padres.

"We're obviously going to be a little careful with him," manager Bruce Bochy said before Wednesday's game against the Padres. "We're going to wait for after Thursday to see where we are with him."

Lincecum said he will leave the decision up to team trainers and Giants management.

"I don't see why I can't start in four days," he said. "I want to pitch but it's not up to me."

Lincecum began feeling some tightness in his back when the team returned from Milwaukee on Sunday night, and it worsened overnight.

"He was disappointed and little frustrated he couldn't pitch," Bochy said. "He's never had anything like this before."

Entering Wednesday's games, Lincecum (13-5) ranked second in the NL in ERA (2.34) behind the St. Louis Cardinals' Chris Carpenter. He was one of five NL pitchers with two shutouts and one of two with four complete games. He led the league with 233 strikeouts and 200 1/3 innings pitched.