San Francisco, CA (Sports Network) - Yorvit Torrealba smacked a two-run homer and Jeff Francis picked up his first win in over two months as the Colorado Rockies edged the streaking San Francisco Giants, 4-2, in the opener of a three-game set.

Francis (4-8), in his fourth start since spending more than six weeks on the disabled list with shoulder inflammation, surrendered just two runs on seven hits, landing in the win column for first time since June 18.

Ian Stewart had two hits and scored twice, and Troy Tulowitzki was 2-for-3 with a triple, a walk and an RBI for the Rockies, who won their eighth game in 10 tries.

Matt Cain (8-10) pitched well but was credited with the loss after yielding three runs on six hits and four walks in six innings, halting the Giants' five-game winning streak. Fred Lewis was 2-for-4 with a triple, a run scored and an RBI, and Randy Winn added three hits in the loss.

The Giants pulled ahead early in the first inning. Winn opened with a base hit and sprinted around on Lewis' triple into the right-field gap.

Bengie Molina's sacrifice fly two batters later gave the Giants a two-run lead, but Torrealba followed up Stewart's second-inning lead-off single with his sixth home run of the year to tie it.

After San Francisco squandered a bases-loaded, no-out opportunity in the third, Tulowitzki tripled home Omar Quintanilla to give Colorado a 3-2 edge.

The Rockies loaded the bases in the eighth and added an insurance run on Jeff Baker's pinch-hit sacrifice fly to left, and the bullpen kept the lead.

Manuel Corpas threw a scoreless eighth and Brian Fuentes shut down the Giants in the ninth to earn his 26th save of the season.