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.

Giants taking it 'day by day' with Wilson

ATLANTA -- Continuing to undergo treatment for inflammation in his throwing elbow, right-hander Brian Wilson might try playing catch Friday but has not been given a timetable for his return to pitching.

"We're going day by day right now," Giants head athletic trainer Dave Groeschner said Thursday, implicitly erasing the initial estimate stating that Wilson might be shelved for two or three days.

Also on Friday, Groeschner plans to discuss Wilson's condition with Dr. James Andrews, the noted orthopedist who examined the closer Wednesday in Pensacola, Fla. After that conversation, the Giants might know more about Wilson's immediate future.

"Brian's one of those guys who has a remarkable ability to recover," Groeschner said. "So I wouldn't put anything past him. But we need to make sure he's healthy."

Groeschner emphasized that placing Wilson on the 15-day disabled list isn't being considered right now.

"If that's what we got from Dr. Andrews, we would have done it yesterday," Groeschner said.

Wilson hasn't pitched since Monday, when Atlanta victimized him to score three ninth-inning runs and secure a 5-4 victory.

Whiteside's face, ego on the mend after slide

ATLANTA -- Giants catcher Eli Whiteside didn't hesitate to poke fun at himself Thursday, one day after he knocked himself woozy with a face-planting slide into second base.

"I think I feel better than I look," Whiteside said.

That was beyond dispute. Whiteside sported scrapes on his forehead and nose, though the wound that caught his teammates' attention was a small, vertical cut above the middle of his upper lip. This prompted several Giants to compare Whiteside to silent film star Charlie Chaplin. Whiteside said that Jonathan Sanchez added to the teasing by finding a photograph of Adolf Hitler on the Internet.

Whiteside plunged into the dirt in the fourth inning and left the game in the seventh with dizziness. After the game, teammates didn't start kidding him until they knew he was relatively OK physically.

"It obviously looked pretty funny," Whiteside said of his slide.