As much as the Giants would love to eliminate their archrivals, their top priority over this final series at Dodger Stadium is to remain healthy for postseason play.

So even though Buster Posey's back spasms were believed to be minor and his exit merely a precaution after eight innings, it's no small thing when an injury involves the NL's leading MVP candidate.

Posey felt something in his back when he hit the bag while trying to beat out an infield tapper, Giants manager Bruce Bochy said. Posey made the safe sign as he hit the bag but first base umpire Paul Emmel ruled that the throw beat him.