"I wasn't moving around too well, but that's it," Jeter said. "I just stiffened up."
Jeter said he suffered the injury in the first inning of New York's 13-inning loss at AT&T Park, legging out a double off right-hander Matt Morris and extending his hitting streak to 17 games.
Visibly hindered as he continued play, Jeter went 2-for-5 with an RBI in the contest. He did not take the field after striking out in the top of the eighth inning, and Torre said that if Jeter had reached base, the Yankees would have pinch-run for him.
"It shouldn't be long," Torre said. "[Sunday] is a possibility. I know he's going to want to play, but we have to do the smart thing with the off-day [Monday]. I don't know what that is."
Miguel Cairo took over at shortstop for the final five innings. Torre called the injury "a mild thing" and noted that Dr. Allen Miller, the club's Tampa-based physician, is on the West Coast trip with the team and examined Jeter in the clubhouse.
Jeter was not sent for further tests and said he would be available to play on Sunday, when the Yankees complete the California leg of their three-city, nine-game road trip.
Jeter is the American League's leading candidate to start at shortstop in the All-Star Game, to be held on July 10 in San Francisco.
He has a 25-game hitting streak in Interleague Play, the longest streak in the Major Leagues. With two hits on Saturday, including his 21st double, Jeter raised his season average to .346.
Bryan Hoch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.