Pirates 5, Cubs 4: Pedro Alvarez and Travis Snider homered to account for all the scoring in a five-run seventh inning as visiting Pittsburgh erased a 4-0 deficit to hand Chicago its seventh straight series loss.

Starling Marte delivered two hits, and scored when Alvarez belted the first offering from James Russell (0-1) over the wall in center for a three-run shot with two outs - his third homer in two days - to give the Pirates a 5-4 lead. Gerrit Cole (2-0) allowed four runs (three earned), five hits and struck out 10 in six innings.

Starlin Castro had three hits, drove in a run and scored another while Welington Castillo added an RBI as the Cubs wasted a strong effort from Travis Wood, who tied a career high with nine strikeouts in six-plus innings. Snider's pinch-hit blast came against Brian Schlitter, who entered after Neil Walker led off the seventh with a double.

Chicago took a 1-0 lead in the third thanks to daring base running by Emilio Bonifacio. The Cubs' lead-off hitter reached with two outs on Cole's fielding error and stole second, and when catcher Tony Sanchez's tailing throw sailed into right-center, Bonifacio didn't stop at third and beat Andrew McCutchen's off-line throw to the plate.

The Cubs added three runs in the fourth, with Castro's RBI single through a drawn-in infield igniting the uprising. Nate Schierholtz scored on a wild pitch and after Mike Olt struck out, Castillo's single to left drove in Castro, whose foot slid directly into Sanchez's glove, but Sanchez was holding the ball in his throwing hand.

GAME NOTEBOOK: Pittsburgh's Mark Melancon worked a perfect eighth and hasn't allowed a home run in his last 68 innings - the longest active streak in the majors - and Jason Grilli recorded his third save when he retired Bonifacio on a grounder with the bases loaded in the ninth. ... The Pirates, who are 7-1-1 in series at Wrigley Field since the start of 2011, won three straight series to open a season for the first time since 1992 (six straight) and the fourth time in the last 50 years (three in 1976 and 1966). ... Pittsburgh continues its stretch of 26 games against Central Division foes to start the season when it begins a three-game series in Milwaukee on Friday while Chicago heads to St. Louis for three.