Recap: San Diego vs. Colorado

San Diego, CA (Sports Network) - Chris Nelson went 3-for-4 with a solo home run and two RBI on Friday as the Colorado Rockies topped the San Diego Padres, 7-4, in the opener of a three-game series at Petco Park.

Wilin Rosario and Jordan Pacheco each had two-run doubles, while Charlie Blackmon added a solo homer for the Rockies, who had lost seven of their last eight coming in. Carlos Gonzalez had four hits and a run scored in the triumph.

Guillermo Moscoso (3-1) earned the win with 1 2/3 scoreless innings of relief behind starter Tyler Chatwood, who allowed four runs on five hits with four strikeouts and two walks over 3 2/3 frames.

Yonder Alonso crushed his first career grand slam for the Padres, who saw their four-game winning streak come to an end. Chase Headley had two hits and a run scored in the setback.

Andrew Cashner (3-4) took the loss after yielding six runs on 10 hits over 3 2/3 innings.

"He wasn't really hitting his spots," Padres manager Bud Black said about Cashner. "They kept putting the ball in play, granted they didn't hit it hard, but they hit it in the right spots."

Colorado jumped on top with five runs in the first inning. Dexter Fowler singled, Josh Rutledge was plunked, and Gonzalez reached with an infield single to quickly load the bases against Cashner.

Rosario doubled into the left-center field gap to plate Fowler and Rutledge, and Pacheco brought home Gonzalez and Rosario with a double into right field. Nelson beat out a single to short two batters later, scoring Pacheco for the 5-0 lead.

"It's rare that you come into Petco Park and throw five runs up there on six hits in the top of the first inning. You don't see that happen too often," Rockies manager Jim Tracy said.

The Padres got four runs back in the home portion of the inning. Will Venable ripped a one-out single, Headley followed with a base hit and Yasmani Grandal walked to load the bases for Alonso, who got a pitch up and crushed it over the wall in left for a grand slam, pulling San Diego within 5-4.

Nelson extended the Rockies lead to 6-4 in the third when he blasted a fastball over the wall in left-center field and Blackmon made it a three-run game in the eighth when he got out in front of a fastball and pulled it over the fence in right field for his second career home run.

Rafael Betancourt allowed a one-out single to Everth Cabrera in the ninth, but fanned Chris Denorfia and got Headley to fly out for his 29th save of the season.