SAN FRANCISCO -- One day after receiving an epidural shot for a bulging disk in his neck, Jose Guillen was back in the Giants' lineup Thursday, batting seventh and playing right field.

Guillen said the neck pain had been lingering, but after Sunday's game in San Diego he decided the pain was too much to bear.

"Something was bothering me for the past two weeks," Guillen said. "I finally had to say, 'That's it.' I had to stop being a tough guy."

Giants manager Bruce Bochy said Guillen was excited in the difference he felt in his neck. Guillen has struggled since being acquired by the Giants on Aug. 13, hitting .280 with one home run and seven RBIs in 26 games. He also had especially struggled of late -- getting only eight hits in his last 44 at-bats -- but Bochy hopes the treatment can revive Guillen.

"He's a tough guy; he really wasn't saying how much it was bothering him," Bochy said. "But we gave him a day and now he's feeling better, stronger and we're hoping he stays that way."

Bochy puts Rentera at leadoff vs. Lilly

SAN FRANCISCO -- Edgar Renteria got the nod Thursday in the revolving door that has become the Giants' leadoff hitter.

Giants manager Bruce Bochy said he decided to bat Renteria leadoff after Wednesday's game, mostly due to Renteria's success against left-handers this season. Renteria is hitting .306 (19-for-62) against lefties this season and also hit a homer in his last start against Thursday's Dodgers starter Ted Lilly.

With the interest in the leadoff spot becoming a hot topic in Andres Torres' absence, Bochy talked Thursday about the time he puts into writing the lineup. Bochy said the lineup card is constantly on his mind, as he and his staff discuss it at length before and after games. Bochy also said he sometimes awakes at 4 or 5 a.m. with an idea.

Bochy, who has tinkered with lineups throughout his four-year tenure with the Giants, admitted this season is the most he's thought about the lineup, mainly due to personnel.

"It's a case where you do spend more time so you do get the matchups you do want and [go] with the hot bats and who you think gives you the best chance against the opposing pitcher," Bochy said.

Bochy said the team's day-to-day results rarely factor into making the lineup card.

"Very little, really," Bochy said. "You look more at the players themselves and how they're seeing the ball and playing, things like that."

Posey likely to play every day down stretch

SAN FRANCISCO -- With the pennant race in full gear, Giants manager Bruce Bochy said Thursday it was possible that rookie catcher Buster Posey could start each of the team's remaining 15 games.

"With the days off, I think he could go every day," Bochy said. "If we wanted to tweak the lineup and put him at first for a game, we could do that. Knock on wood, it's all good with him and he could go back there every day."

Since being recalled on May 29, Posey, a National League Rookie of the Year candidate, has started 90 of the Giants' 93 games, 60 of which have come behind the plate. The Giants have two remaining off-days on Monday and Sept. 27.

Entering Thursday, Posey was hitting .324 with 13 homers and 59 RBIs. Perhaps just as important, however, has been Posey's ability to work with the pitching staff, which was the only moderate question mark when he was handed the everyday catching job when incumbent Bengie Molina was traded.

Interestingly, Giants pitchers haven't experienced any dropoff with Posey behind the plate. Entering Thursday, San Francisco's pitching staff had posted a 3.44 ERA in the 60 games Posey caught, compared to a 3.50 mark in 58 games with Molina.

"How comfortable he is handling this staff is not so much a surprise, but it's not easy transitioning for pitchers in the middle of the season," Bochy said. "It's gone well, and that's a credit to his concentration back there and handling the staff."

Sandoval out against lefty pitchers

SAN FRANCISCO -- As he alluded to Wednesday night, Giants manager Bruce Bochy kept Pablo Sandoval out of Thursday's series finale against the Dodgers.

And with Dodgers left-hander Ted Lilly throwing Thursday and the Brewers scheduled to start lefties Randy Wolf and Chris Narveson during the weekend, Bochy hinted Sandoval could be seen more on the bench in the coming days.

"It could be a couple [games]," Bochy said. "I talked to Pablo a few minutes ago and told him what the plan was. We'll see how it goes tonight. It's fair to say he's not swinging as well from that side."

Sandoval has struggled all season from both sides of the plate -- hitting .276 against right-handers and .228 against lefites -- but prior to this week his saving grace had been his .327 home average, which was the seventh-best in the National League.

Even that wasn't seen this week in the first two games against the Dodgers, as Sandoval was hitless in his last 15 at-bats.

Worth noting

Freddy Sanchez was back in Thursday's lineup and is fine, manager Bruce Bochy said. When asked about Sanchez's health, Bochy said, "I don't think he's less than 100 percent; if he is, it's maybe just a little bit." ... A win Thursday would give the Giants a win in the season series against the Dodgers for the first time since going 10-9 in 2005. ... Thursday starter Jonathan Sanchez entered Thursday's game with a 12-inning scoreless streak, three innings shy of matching his career-long mark, which was set April 14-25, 2008. ... Shortstop Juan Uribe entered Thursday with a six-game hitting streak in which he's batted .450 (9-for-20).