Updated

For as well as the San Diego Padres have been playing lately, Andrew Cashner really put his club in a tough spot.

Cashner struggled from the outset and the Colorado Rockies jumped all over the right-hander.

Rookies Wilin Rosario and Jordan Pacheco had consecutive two-run doubles in the first inning to lead the Rockies to a 7-4 win over the Padres on Friday night.

Carlos Gonzalez tied his career high with four hits. He also stole two bases to become the first Rockie to reach the 20-20 club in three consecutive seasons.

Rookie Yonder Alonso hit a grand slam in the first inning for San Diego, which had won seven of eight overall and 11 of its previous 13 at home. But the Padres could never recover.

"It was a battle out there to try and make pitches," Cashner said. "I couldn't catch a break. I kind of put us in too big of a hole. I couldn't really get us out of it."

Cashner (3-4) allowed Chris Nelson's solo homer in the third before he got yanked with one out in the fourth.

"I think the story was he wasn't really hitting his spots," Padres manager Bud Black said. "They were putting the ball in play."

Rookie Charlie Blackmon also hit a solo homer as the Rockies won for just the third time in 11 games.

Rosario and Pacheco's big hits keyed a five-run first inning in which Colorado sent 10 men to the plate against Cashner.

"Offensively, our first inning was one of our better ones," Rockies manager Jim Tracy said. "We needed to get someone on base and we did."

Cashner lasted just 3 2-3 innings, giving up six runs on 10 hits. The right-hander was making his second start since coming off the disabled list on Sept. 1.

"It was tough," Cashner said. "I couldn't stop them. I've got to find a way to minimize next time."

Colorado (58-85) needs to win 10 of its final 19 games to avoid tying the club's worst record at 67-95.

Guillermo Moscoso (3-1), the second of five Rockies relievers, allowed two hits in 1 2-3 scoreless innings. Rafael Betancourt pitched the ninth for his 29th saves in 34 chances.

After San Diego cut the Rockies' lead to 5-4 in the first inning, Nelson gave the Rockies a 6-4 lead with a solo homer, his ninth, in the third inning. Blackmon hit his first homer in the eighth off Brad Boxberger.

Colorado scored five runs in the first as the first five players reached base safely in an inning that included three infield singles and a hit batter.

After the Rockies loaded the bases, Rosario hit a ball that short hopped the wall in left center for a two-run double. Pacheco then doubled in two more runs. Nelson's high chopper with one out went for an infield single to drive in the final run.

The Padres got right back in the game as Tyler Chatwood allowed one-out singles to Will Venable and Chase Headley before loading the bases by walking Yasmani Grandal. Alonso followed by hitting a 2-1 fastball into the left-field stands for his first career grand slam.

NOTES: Cashner got his first big-league hit with a bunt single in the second. .. Starting Friday night, Colorado closes out the season with 20 consecutive games. ... San Diego radio announcer Jerry Coleman celebrated his 88th birthday Friday. The Padres have a pre-game ceremony scheduled Saturday to honor Coleman's 70 years in baseball. ... Rockies LHP Jorge De La Rosa is scheduled to make his third rehab start for Single-A Modesto on Saturday night in Game 3 of the California League Championship Series against Lancaster. Colorado would like De La Rosa to start a major league game before the end of the season. De La Rosa hasn't pitched in the majors since he underwent Tommy John surgery in June 2011. ... Padres LF Carlos Quentin's sore right knee kept him out of the starting lineup for the third straight game. ... Rockies LHP Drew Pomeranz (1-8, 4.80) faces Padres RHP Casey Kelly (1-1, 7.07) on Saturday night.