Ruf (hamstring) is scheduled to undergo an MRI on Thursday, Susan Slusser of the San Francisco Chronicle reports.
Ruf went 2-for-3 with a pair of base hits before he was removed from Wednesday's 5-4 win with an apparent right hamstring injury. Jason Vosler came on to replace Ruf and supplied a go-ahead solo home run in the eighth inning to lift the Giants to victory. With all of Brandon Belt (oblique), Wilmer Flores (hamstring) and Tommy La Stella (hamstring) on the injured list, Ruf will likely be in line for steady reps at first base if his own hamstring issue doesn't prove to be too significant. The Giants should have a better idea of Ruf's recovery timeline once the results of the MRI are read.