SAN FRANCISCO -- Right-hander Matt Cain will skip his previously scheduled start Monday, the Giants decided following Saturday's pregame bullpen session to test his strained right hamstring.
Reliever Yusmeiro Petit (3-1, 4.76 ERA) will make the start. Three of his last five appearances have been starts.
"We think he needs a little more time," manager Bruce Bochy said of Cain. "He did a light bullpen. He still feels it a little bit. It's not worth the risk."
The Giants do not intend to place Cain on the disabled list, Bochy added.
Cain (1-3, 3.36 ERA) sustained the injury during his last start, resulting in some soreness.
Willie Bans is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.