Molina, who is eligible for free agency this offseason, homered twice and drove in four runs Tuesday night to lead the Giants to an 8-4 victory over the Arizona Diamondbacks that kept San Francisco's slim wild-card hopes alive.
"We don't know what's going to happen and Bengie doesn't know what's going to happen," San Francisco manager Bruce Bochy said. "I do know he's done a great job here. We wouldn't be in this position ... without Bengie. He's going to be fine no matter what happens."
Pablo Sandoval had four hits and two RBIs for the Giants, who trail NL wild card-leading Colorado by five with five games left. The Rockies beat Milwaukee 7-5 in 11 innings.
Playing in what could be his last home series with the Giants, Molina had one of his best nights at the team's waterfront stadium after sitting out the previous three games with bruised fingers on his left hand. San Francisco's popular catcher matched his season high with four RBIs and went deep twice for the second time this year, giving him a career-high 20.
Molina, 35, hit a two-run homer off Doug Davis in the fourth and followed Sandoval's two-run shot in the seventh with a drive off Clay Zavada.
But the Giants need to add more offense and have 2008 first-round draft pick Buster Posey, who hit .325 with 18 homers and 80 RBIs in the minors this year, waiting to take over behind the plate.
"Hopefully he'll get back with us and help us like he has the last three years," winning pitcher Jonathan Sanchez said. "The way he handles the pitching is amazing."
Molina wasn't in the locker room when reporters were allowed in after the game.
Miguel Montero homered twice, including a two-run drive into McCovey Cove in the sixth, for Arizona.
"We gave them a lot of baserunners and allowed them to create rallies," Diamondbacks manager A.J. Hinch said. "We couldn't get out of anything. We always felt like we were one out away from getting out of something but with two outs they never let up. Sandoval and Molina were the difference in the game."
Sandoval had two singles, a double and his 23rd homer to raise his average to .329. He also scored four times.
Sanchez (8-12) retired 11 of the first 13 batters he faced before yielding Montero's two-run homer in the fourth. The next batter, Ryan Roberts, hit what was initially ruled a homer before umpires, using instant replay, changed it to a ground-rule double.
Left fielder Andres Torres appeared to catch the ball after leaping at the fence, but it popped out of his glove and landed on top of the wall momentarily before dropping off. Torres, who had fallen on his back on the warning track, reached up and grabbed the ball out of the air but third base umpire Dana DeMuth signaled home run.
Bochy came out to protest and the umpiring crew left the field briefly to view the replay before returning and changing the call to a double. Sanchez then retired Rusty Ryal to end the inning.
Sanchez allowed three runs and five hits in 5 1-3 innings. Bob Howry, Dan Runzler, Jeremy Affeldt and Sergio Romo combined to finish the seven-hitter.
"We're still breathing," Bochy said. "There's a little hope, not a lot."
Montero's towering drive in the sixth was the first ball hit into McCovey Cove by a Giants opponent this season and cut San Francisco's lead to 4-3. Montero picked up his first multihomer game of the year and third of his career.
"It was like a home run derby," Montero said. "It was a long game, it was miserable because it was too long and it looked like the ball was flying today."
Sandoval doubled leading off the bottom half and scored on a single by Molina.
Davis (8-14) beat San Francisco a week earlier when he went 7 1-3 innings but the left-hander wasn't nearly as sharp this time. He gave up seven hits and walked five in four innings while losing for the sixth time in his last eight starts.
Eugenio Velez scored on a wild pitch in the first and Aaron Rowand drew a bases-loaded walk to give the Giants a 2-0 lead.
NOTES: The Diamondbacks fell to 2-8 at AT&T Park this season. ... Sanchez is 3-1 with a 2.59 ERA in five starts and one relief appearance against Arizona in 2009. ... Roberts is batting .400 (10 for 25) over his last eight games. ... Davis singled in the third, his 10th hit of the year. ... Arizona RHP Daniel Cabrera pitched a scoreless eighth and has not allowed a run in his last three outings.