ATLANTA -- Manager Bruce Bochy wants Giants pitchers to close the vast gap between their performance on the road and at home.

San Francisco entered Tuesday with a 4.85 road ERA, third-highest in the Majors, compared to 2.31 at AT&T Park. The disparity was especially pronounced on the Giants' previous trip, when they yielded 41 earned runs in 49 2/3 innings while losing five of six games at Washington and Pittsburgh. That's an ERA of 7.43.

"That's a little too extreme," Bochy said. "That is too dramatic [a difference]."

Seven pitchers began the current trip with road ERAs exceeding their home ERA by more than two runs: Jeremy Affeldt (1.29 home, 3.86 road), Madison Bumgarner (1.81, 4.43), Santiago Casilla (1.83, 4.40), Tim Lincecum (3.43, 9.00), Javier Lopez (1.13, 5.73), Ryan Vogelsong (1.43, 3.59) and Tuesday's starter, Barry Zito (3.09, 5.19).

Giants hopeful Sanchez's knee injury minor

ATLANTA -- Giants catcher Hector Sanchez hopes to avoid the disabled list despite spraining his left knee during San Francisco's 9-0 victory Tuesday night over the Atlanta Braves.

"The doctor told me he saw nothing serious," said Sanchez, who was examined by team orthopedist Ken Akizuki. Sanchez will undergo a MRI on Wednesday morning to determine the extent of the injury.

Manager Bruce Bochy said that he believes Sanchez could be sidelined for nothing more than "a couple of days." Bochy added that the organization did not immediately summon a catcher from the Minor Leagues to be on hand Wednesday in case Sanchez's injury is worse than believed. And Buster Posey said that he can handle catching Thursday afternoon's series finale following Wednesday night's game. Until Sanchez is cleared to play, Pablo Sandoval will serve as San Francisco's emergency catcher.

After singling to right field with nobody out and Angel Pagan on first base in the fourth inning, Sanchez hurt himself as he returned to the base when Braves pitcher Jair Jurrjens lobbed a pickoff throw. Sanchez tried running after time was called to test his leg, but left the game in obvious discomfort.

"It hurt so bad," he said. "When I tried to run, I couldn't."

Sanchez admitted that he initially felt discomfort in the knee last weekend.

"But it wasn't too bad," he said. "It was a little bit sore."

Sanchez is batting .281 in 39 games, including 30 starts, with two home runs and 24 RBIs.

Posey confident as Sanchez stays in lineup

ATLANTA -- Without defying manager Bruce Bochy, catcher Buster Posey insisted Tuesday that he's capable of handling any of the Giants' starting pitchers effectively. That includes the pair that he has collaborated with less often lately, Tim Lincecum and Barry Zito.

"I've got the utmost confidence in myself to catch anybody. So I'd never question that," Posey said. "I've caught Timmy plenty and had lots of success with him. I really haven't caught Zito as much as Timmy, but I'm definitely comfortable with him as well."

Last Friday, Bochy indicated that Posey would catch Zito in Tuesday's series opener here against the Atlanta Braves, since Sanchez was to form Saturday's battery with Lincecum. Since Sanchez went 4-for-6 Saturday, Bochy wanted both him and Posey in the lineup behind Zito.

So Sanchez caught, as he has done in each of Zito's outings, while Posey played first base, sending Brandon Belt to the bench. That arrangement lasted until the fourth inning, when Sanchez sprained his left knee -- apparently as he tried to stop himself after breaking from first base. Sanchez left the game, prompting Posey to take over behind the plate with Belt entering as a pinch-runner and staying in to play first.

Sanchez also caught Lincecum's seven shutout innings against the Dodgers on June 27, as well as the right-hander's eight scoreless frames last Saturday.

Posey, whose 60 starts at catcher doubles Sanchez's 30, did not question Bochy's use of personnel. "I think ultimately anything Bochy does, he's going to do it because he feels like it's going to give the team the best chance to win. That's what it's all about," Posey said before the game. "Hector's been doing a good job. He's been swinging the bat well. It's good to have his bat in the lineup."

Posey expressed appreciation for the dialogue Bochy maintains, notifying him how he'll be used. "Bochy's great with communicating with me," Posey said.

Said Bochy, "I like to keep him informed about what the plan is, to help him prepare."