De La Rosa pitched into the seventh inning, but the Diamondbacks struggled against Chris Heston and lost 4-1 to the slumping San Francisco Giants on Saturday night. Once a top prospect in the Los Angeles Dodgers organization, De La Rosa continues to make progress three years after undergoing Tommy John surgery. De La Rosa left a ball up and over the plate to Brandon Crawford, who connected for a two-run homer that made it 4-1 in the fourth. Joe Panik had three hits and drove in a run as San Francisco snapped an eight-game losing streak. Buster Posey went 2 for 4 with an RBI single on the same night that the Giants received their World Series rings for last year's title. Nori Aoki also had two hits, including a leadoff double in the first that led to the Giants' first run and sent them on their way to their first win at home. Diamondbacks: C Gerard Laird (lower back tightness) is eligible to come off the disabled list when Pittsburgh visits Phoenix on Friday. Giants: RHP Jake Peavy was placed on the 15-day disabled list before the game with a back strain.