SAN FRANCISCO — It might have been the slowest home run trot in major league history, but Bengie Molina meant no disrespect.

He simply couldn’t go any faster.
But Molina certainly quickened hearts on a chilly night at China Basin. Unable to start the past two games because of a strained quad, Molina came off the bench and delivered a three-run home run in the eighth inning, sending the Giants to a sudden and significant 4-3 victory over the Arizona Diamondbacks on Wednesday night.
Molina, pinch hitting for Ryan Garko, drilled an 0-2 slider from Chad Qualls high into the foggy air, and after a seemingly interminable wait, it settled into the first row of the left field bleachers.
A small crowd of 27,645 erupted and wouldn’t stop chants of “Ben-gie” until Molina acknowledged them with a curtain call.
Worn down by a heavy workload over the weekend at Coors Field and miscast for two seasons in the cleanup spot, Molina’s swing might have been his biggest in three years as a Giant.
It made a winner of Justin Miller, who pitched a scoreless eighth inning in relief of Jonathan Sanchez. Miller, who heard scattered boos, was pitching for the first time since he fueled a crushing defeat Monday at Coors Field in which he walked Rockies pitcher Adam Eaton. Miller hadn’t retired any of the last nine Rockies hitters he faced.
With closer Brian Wilson unavailable after throwing 70 pitches over the previous two nights, Brandon Medders retired the final three hitters — against his former team, no less — to record his first career save.
The Giants took their team photo Wednesday afternoon. Then they took the field knowing that with the Los Angeles Dodgers in Colorado, a victory would improve their playoff picture one way or the other.
As it turned out, the Dodgers won, allowing the Giants to move within three games of the Rockies in the wild-card race.
Soft-tossing left-hander Doug Davis, a Northgate High product, dominated over the first seven innings, but Edgar Renteria started a two-out rally when he worked a seven-pitch walk. Randy Winn hit a soft single to drive Davis from the game, and Qualls’ third slider stayed in Molina’s happy zone.
Molina’s listed injury was a strained quadriceps, but he also had swollen fingers on his catching hand and was physically worn down after playing four grueling games at Coors Field.
The Giants also were missing Pablo Sandoval for the second consecutive night. Sandoval’s bruised right calf was improved, but he came down with a respiratory ailment.
The Giants erred on the side of caution with Sandoval, hoping to freshen him up for this weekend when the Rockies arrive for a three-game series. But as they’re discovering, it’s a difficult existence when your best hitter has conditioning issues and your cleanup man is paying a physical toll behind the plate.
Eli Whiteside replaced Molina and worked with Sanchez for the second time since catching his no-hitter July 10. This time, Whiteside had a tougher time behind the plate.
Diamondbacks leadoff hitter Ryan Roberts hit an 0-2 fastball into the left field bleachers for a home run.
The next batter, Augie Ojeda, reached base when the third strike got away from Whiteside and he bounced his throw to first base. It shouldn’t have been a tough scoop for Ryan Garko, but he failed to pick it and Whiteside was charged with an error.
Whiteside committed his second error of the inning when Ojeda stole second base and the throw sailed into center field. But Sanchez made a nifty escape, striking out Justin Upton and Miguel Montero to strand Ojeda.
Whiteside failed to block two other wild pitches, including a critical one that led to some busted strategy in the Diamondbacks’ two-run sixth inning.
Upton drew a one-out walk, and with a base open following a wild pitch, Giants manager Bruce Bochy had Sanchez issue an intentional walk to rookie Rusty Ryal. Bochy wanted the left-handed matchup against rookie Gerardo Parra, who lined a single to score Upton. Alex Romero, also a left-handed hitter, bounced another single up the middle that scored Ryal.
It’s hard to go by the book with these Diamondbacks hitters. It’s more of a leaflet.