The left-hander, though, appears to be back to his old self if his latest outing is any indication.De La Rosa looks to build on an impressive performance as the surging Rockies go for an eighth consecutive win Saturday night in the second of three against the visiting Diamondbacks.After recording a 6.10 ERA in his first two starts, De La Rosa (1-1, 3.86 ERA) allowed two hits and struck out seven over six scoreless innings Sunday in a 2-1 victory at San Diego. De La Rosa earned his first win since May 13, 2011 -- 11 days before he tore the collateral ligament in his throwing arm versus Arizona."That's nothing new to us," Padres manager Bud Black told MLB's official website. "We've seen Jorge throw that way before, prior to his Tommy John surgery."A 16-game winner in 2009, De La Rosa could have a big impact this season as long as his arm holds up."It was real special," he said of Sunday's win. "It was a very hard time last year and the year before. I have to keep focus in every game I pitch and try to be the same guy as I was before."Despite that forgettable day nearly two years ago, De La Rosa is surely looking forward to facing the Diamondbacks. He's gone 6-2 with a 2.28 ERA over his last 10 starts in the series while striking out 57 in 59 1/3 innings. De La Rosa has limited Gerardo Parra to two hits in 12 at-bats in their matchups and Martin Prado is 0 for 5.De La Rosa will look to follow Jhoulys Chacin's strong effort in Friday's 3-1 series-opening win. Chacin pitched effectively into the seventh inning before leaving with left oblique tightness. He became the first Rockies starter to throw 100 pitches since June 12, a stretch of 117 games -- the longest such streak since records started being kept in 1988."We hope it's nothing serious," third baseman Chris Nelson said. "But when you see your pitcher walk off the mound like that, it's a rough one for the whole team."Despite going 0 for 2 with runners in scoring position, Colorado (12-4) is batting .359 in such situations during its run. The Rockies haven't posted eight consecutive victories since a 10-game winning streak Sept. 3-12, 2010.Colorado is also a franchise-best 7-0 at home, where it's outscored opponents 51-22.Arizona (9-7), meanwhile, has hit just .221 while opening 1/3 on its nine-game road trip. Prado, Paul Goldschmidt, Miguel Montero and Cody Ross -- the team's 2-3-4-5 hitters Friday, went a combined 0 for 16. Goldschmidt had reached base in all 15 games before coming up empty.The Diamondbacks try to get back on track behind Trevor Cahill (0-2, 3.50), who threw 7 1/3 innings of six-hit ball Sunday in a 1-0 walkoff win over the Los Angeles Dodgers."Cahill was outstanding -- he's tough, he pounds the strike zone, as tough as anybody we face," Dodgers catcher A.J. Ellis said. "He has movement on the ball and deception."Cahill, in contrast, hasn't been very sharp over five career starts against the Rockies, going 1/3 with a 5.65 ERA. Dexter Fowler is 4 for 5 with two triples against him, but Michael Cuddyer is 1 for 14.