Chicago, IL -- (Sports Network) - Alfonso Soriano hit a pair of home runs and drove in four, as Chicago bested Pittsburgh, 7-4, in the opener of a three- game weekend set from Wrigley Field.

"I feel very comfortable. If I see a strike, I want to hit the ball very hard," said Soriano. "I have my confidence back. I'm playing 100 percent now. I feel good."

Geovany Soto and Mark DeRosa also went deep for the Cubs, winners in seven of their last eight games.

Sean Gallagher (1-0) earned his first major-league win for Chicago, scattering four hits and one run over six innings. The 22-year-old walked three and struck out three, needing 91 pitches to complete the outing.

"Breathtaking. No words really come to mind," Gallagher said of earning his first big-league victory. "I'm just thankful to be there. I'm just going to take it every fifth day, go out there and give the team the best I can, and every fifth day just keep piling on."

Doug Mientkiewicz and Jason Bay homered for the Pirates, who have dropped two of three overall. Nate McLouth doubled and scored while Xavier Nady also drove in a run.

Pittsburgh starter Tom Gorzelanny (3-4) took the loss, charged with seven hits and seven runs over six innings, giving up four home runs.

The Cubs blitzed Gorzelanny with six runs in the first two innings to take a commanding 6-0 lead.

Soriano began the contest with a homer reaching just over the bleachers in left, then Ryan Theriot singled and stole second. He scored on an Aramis Ramirez groundout to first, and Soto followed with a solo blast.

In the second, DeRosa doubled and Reed Johnson singled. Both runners moved up on Gallagher's sacrifice bunt, and Soriano launched his second of the game into the left-center-field seats.

"I hope I don't face them again. I've had a string of bad outings against them," Gorzelanny said of the Cubs, who have ripped him for 21 runs in 11 innings already this season. "Next time I face them, I'll go out there and give everything I have. Right now I'm focused on my next game."

Pittsburgh finally broke through in the sixth, as McLouth led off with a double and scored on Nady's single, but DeRosa offset the run with a solo homer to right in the home half.

Bob Howry, who entered the game for Gallagher in the seventh, ran into trouble in the eighth, allowing the Bucs to come within 7-4 on Bay's one out home run and a two-out, two-run blast by Mientkiewicz.

Kerry Wood retired the side in order in the ninth to preserve the win and earn his ninth save.

Game Notes:

The Cubs have beaten the Pirates seven straight times this season and have won 10 in a row over Pittsburgh since last September...It was Soriano's first multi-homer game of the season...Mientkiewicz recorded his first longball of the campaign.