Padres 4, Rockies 3: Jesus Guzman delivered a pinch-hit walk-off single as host San Diego stormed back against Colorado.Todd Helton gave the Rockies a 3-2 lead with a leadoff home run in the top of the ninth but Chase Headley matched him in the bottom of the frame, sending Rex Brothers' 2-0 fastball out to left to knot it back up. The Padres loaded the bases on a walk, a bunt single and an intentional walk before Guzman sent a slider from Brothers (2-1) into left to plate Kyle Blanks with the winning run.Huston Street (2-4) left a first-pitch fastball up to Helton, who hammered it over the center-field wall for his 13th home run. Will Venable added a solo blast for San Diego, which has won three of four.The Rockies started the game with three straight hits, capped by Troy Tulowitzki's RBI double. Michael Cuddyer followed with a run-scoring fielder's choice to give Colorado a quick 2-0 edge.Venable led off the bottom of first and cut the deficit in half with a line drive over the wall in right. The Padres drew even in the sixth, when Helton tried to turn a double play by firing across the diamond to third and had the throw sail wide, allowing Chris Denorfia to score.GAME NOTEBOOK: San Diego starter Burch Smith allowed two runs on four hits while striking out seven. Rockies starter Juan Nicasio was charged with two runs (one earned) on four hits in six innings. … Colorado 3B Nolan Arenado (thumb) was held out of the starting lineup, but he entered the game as a defensive replacement in the ninth. … Rockies RHP Roy Oswalt (left hamstring) was activated from the disabled list and is expected to pitch on Sunday behind rookie Chad Bettis.