ATLANTA -- Jonathan Sanchez will test his sprained left ankle by throwing on flat ground Friday, a session that likely will determine whether the left-hander can start Sunday at Houston.
Sanchez expressed confidence that his ankle will be strong enough to withstand the rigors of throwing.
"If I can press and push, I'll be fine," he said.
Sanchez hurt himself while attempting to field a third-inning bunt in Tuesday's game against the Braves.
Giants manager Bruce Bochy said he felt "optimistic" that Sanchez will be able to start Sunday. Bochy said that if Sanchez can't pitch against the Astros, he'll probably be replaced by either Dan Runzler or Guillermo Mota. That decision, in turn, would hinge on which pitcher is fresher entering Sunday, since San Francisco has three more games before that date.