CHICAGO (AP) — Carlos Silva pitched six strong innings to remain unbeaten and the Chicago Cubs overcame Todd Helton's first home run of the season to beat the Colorado Rockies 6-2 on Tuesday night.
Tyler Colvin had three hits and fellow rookie Starlin Castro drove in two runs for the Cubs, who have a three-game winning streak. With the two-game sweep of the Rockies, Chicago won a series for only the fourth time this year.
Silva (5-0) allowed two runs on six hits in joining the Yankees' Andy Pettitte and Phil Hughes and San Francisco's Tim Lincecum as the majors' 5-0 pitchers.
Silva had been a high-priced bust for Seattle, where he went 5-18 with a 6.81 ERA in two years. The Mariners insisted the Cubs take him in December's deal for troubled outfielder Milton Bradley.
The 31-year-old right-hander opened the seventh by walking Troy Tulowitzki, his only free pass of the game. After Cubs trainer Mark O'Neal made a brief visit to the mound for an unspecified reason, Silva gave up Helton's shot into the right-field bleachers to cut Chicago's lead to 3-2.
Helton's first home run since Sept. 30 gave him nine RBIs this season. He averaged 35 homers and 118 RBIs in his first seven full years with the Rockies but only 15 and 73 over the last five years.
Reliever Esmailin Caridad then walked Miguel Olivo on four pitches before James Russell came on to retire the side on two strikeouts and a pop-up.
Rockies starter Jhoulys Chacin (2-2) allowed three runs on five hits and five walks in 5 2-3 innings. After pitching 14 1-3 scoreless innings in winning his first two starts, the 22-year-old rookie has given up nine runs over 10 2-3 innings in two losses.
The Cubs went up 3-0 in the fourth. Aramis Ramirez walked, went to third on Marlon Byrd's hit-and-run single and scored on Colvin's single. Soto walked to load the bases, Byrd scored on Castro's grounder and Kosuke Fukudome added an RBI single.
NOTES: Silva also won his first five decisions in 2004, when he was with Minnesota. He became the first Cub to start 5-0 since Greg Maddux in 2006 and the first starter to begin his Chicago career with five wins since Mark Clark in 1997. ... Castro's RBIs were his first since he drove in six runs in his May 7 big-league debut. ... Olivo left the game in the seventh after landing face-first in the dirt while stealing second base. ... Rockies CF Carlos Gonzalez extended his hitting streak to 12 games.