Giants' Sanchez out with twisted knee

PHOENIX -- San Francisco Giants second baseman Freddy Sanchez left Monday night's game against Arizona in the first inning with a twisted left knee.

Sanchez was helped off the field immediately after Mark Reynolds of the Diamondbacks hit a two-run home run with two outs in the bottom of the inning. Sanchez may have been hurt on the previous play when Justin Upton flied out to center field.

Kevin Frandsen replaced Sanchez, who was acquired by the Giants in a trade with Pittsburgh on July 30. There was no word on how long Sanchez could be sidelined.