SAN FRANCISCO -- Buster Posey was not in the lineup for Thursday's series opener against the Braves, missing his second straight game with a tight right hamstring.

"This was a close call," manager Bruce Bochy said before the game. "He's available to pinch-hit, and if something happens we can throw him in the game. We could have done it yesterday."

Posey went through treatment and tests before the game with head athletic trainer Dave Groeschner, and despite noted progress, the Giants decided to sit their All-Star catcher and start Hector Sanchez to catch starter Barry Zito.

"Just talking to [Groeschner] -- he thinks it's the smartest thing to do with 38 games to go," Posey said. "I'm definitely feeling better today."

Posey said the hamstring issue only affects him when he is running and not while he is squatting to catch. He added that he hadn't had a hamstring issue before in his playing career.

"He's not 100 percent, and it's not worth the risk," Bochy said. "We'll give him another day. This is being cautious right now."

Posey echoed that not starting Thursday was out of precaution, and he expects to return Friday.

"I'm hoping tomorrow," Posey said. "I don't see any reason why not."

Peguero replaces injured Christian on Giants' roster

SAN FRANCISCO -- The Giants called up outfielder Francisco Peguero from Triple-A Fresno on Thursday and placed outfielder Justin Christian on the disabled list with a left wrist sprain.

Christian injured his wrist in Wednesday's 8-4 win against the Dodgers after joining the Giants from Fresno following Melky Cabrera's suspension.

"The good news there is nothing is broken or damaged, but he's going to be out four to five days," manager Bruce Bochy said.

Peguero, who has yet to play in a Major League game, was expected to join the team around an hour before the start of Thursday's game. The 25-year-old Peguero joins the Giants after hitting .272 for Fresno and had a 22-game hitting streak end Wednesday.

"He's a strong kid and he's a good outfielder with a good arm; he runs well," said Bochy, who has seen Peguero play during several of the past Spring Trainings. "He's been swinging the bat well. This is an easy one for us."

Arias sits in favor of Crawford vs. Braves righty

SAN FRANCISCO -- With the Braves starting right-hander Tommy Hanson on Thursday, the Giants had regular starter Brandon Crawford at short instead of Joaquin Arias, who has been on fire at the plate as of late.

Arias had a career-high five RBIs in Wednesday's 8-4 win against the Dodgers and is hitting .447 with 11 RBIs in his last 17 games.

"[Hanson] has been tough on righties, so it's nice to have him come off the bench," manager Bruce Bochy said.

Crawford has also picked up his production at the plate recently, hitting .378 (14-for-37) in his last 12 games.

"Crawford has done such a great job, and to get the time off helps him," Bochy said.

Giants pay tribute to retiring Chipper

SAN FRANCISCO -- The Giants honored Chipper Jones before Thursday's game to open the four-game series against the Braves, which marks Jones' final regular-season series in San Francisco.

"I think when you talk about all-time third basemen, Chipper Jones, his name is going to be up there," manager Bruce Bochy said. "He's a great player on both sides of the ball, clutch hitter, he's consistent. It's amazing if you look at the numbers how consistent he's been throughout his career. There's really nothing he couldn't do. He could steal a base, play third, he's a switch-hitter, power from both sides, good hitter."

The 19-year veteran and eight-time All-Star has hit .293 in 114 career games against the Giants, and Bochy has managed against Jones since 1995 with the Padres.

"He's had a tremendous career, and I've always appreciated the talent that he's had and watching him play and how hard he plays," Bochy said.