Recap: Chicago Cubs vs. Pittsburgh

Chicago, IL (Sports Network) - Starlin Castro hit a three-run home run and drove in four, leading the Chicago Cubs to a 7-4 victory over the Pittsburgh Pirates in the opener of a four-game set.

Anthony Rizzo knocked in a pair of runs and Luis Valbuena scored three times for the Cubs, who have won six of their last seven.

Chris Rusin (1-2) did enough to earn his first big league win, limiting the visitors to two runs and four hits over five-plus innings. He fanned six and didn't walk a batter.

"It felt real good, except for that cold beer shower," Rusin said. "I got ahead of a lot of hitters, kept the ball down and located well."

Carlos Marmol turned in a scoreless ninth for his 20th save.

Pedro Alvarez knocked in two runs, while Andrew McCutchen homered and Gaby Sanchez added an RBI for the Pirates, who extended their season-high losing streak to seven games.

James McDonald (12-8) didn't make it out of the fourth and was charged with five hits and four runs with four walks over 3 2/3 frames.

The Bucs climbed within 4-3 in the top of the sixth on an RBI single from Sanchez and a run-scoring fielder's choice grounder from Alvarez, but the Cubs seized the momentum again in the home half as Castro's three-run blast to left field made it 7-3.

"I thought I could jump on the first pitch because I knew he throws fastballs," Castro said. "This team might not be going anywhere, but we still have to finish strong, play well, make the most of our chances."

Valbuena began the rally with a one-out walk against Tony Watson and Alfonso Soriano was hit by a Jared Hughes pitch before the deciding longball.

McCutchen cleared the wall in right field with two down in the seventh, but Shawn Camp retired the side in order in the eighth and Marmol overcame plunking pinch-hitter Alex Presley in the ninth to complete the victory.

The Cubs picked up a run in the third as Valbuena hit a leadoff double, moved up on a Rizzo groundout and scored on a two-out single from Castro.

Chicago tacked on three more in the fourth. Walks to Darwin Barney, David DeJesus and Valbuena loaded the bases and chased McDonald from the game before Rizzo greeted Justin Wilson with a two-run double and Soriano plated another with an infield hit.

"I didn't have any of my pitches going. but I've been in plenty of situations where I didn't before," said McDonald. "That many walks are unacceptable. I should have gotten that out and been in the dugout."