ST. LOUIS -- The Giants remained cautious with Matt Cain's strained right hamstring, as manager Bruce Bochy announced Friday that the right-hander will not make his scheduled start Saturday.
Instead of facing the St. Louis Cardinals, Cain will be placed on the 15-day disabled list retroactive to May 22, the day after he injured himself while pitching at Colorado. Bochy said Cain will be activated next Friday to face the New York Mets at AT&T Park.
Bochy said right-hander Yusmeiro Petit will replace Cain on Saturday against St. Louis. The Giants also announced that Cain's roster spot will be filled by outfielder Juan Perez, who officially will be recalled Saturday.
This will be Cain's fourth missed start due to injury. A cut on his right index finger sent him to the disabled list in late April and forced him to skip two starts. The Giants are exercising similar care with his hamstring, a delicate area for many athletes once it's injured.
The Giants might literally and figuratively have removed the wraps from Cain if this were a crucial game.
"If this were September, he probably would start," Bochy said.
But, said Bochy, "We're going to take the safe route and wait a few more days until we're convinced that he's 100 percent over this."
Bochy said Cain has recovered nicely overall but recently felt "a little something" in the hamstring. "We don't want to put him in a situation where he's at risk of reinjuring this," Bochy said.
Cain, the Giants' No. 2 starter, is 1-3 with a 3.66 ERA in eight games.
Chris Haft is a reporter for MLB.com. Read his blog, Haft-Baked Ideas, and follow him on Twitter at @sfgiantsbeat. This story was not subject to the approval of Major League Baseball or its clubs.