Matt Duffy and Frank Schwindel each hit a grand slam, and the Chicago Cubs rallied for an 11-8 win over the visiting Pittsburgh Pirates on Sunday afternoon.

Duffy added a solo shot and Jason Heyward also homered for the Cubs, who completed a four-game sweep against the Pirates and won their sixth straight contest overall.

Bryan Reynolds hit a grand slam in a losing effort for the Pirates. Yoshi Tsutsugo had a solo home run for Pittsburgh, which has dropped six in a row.

Cubs right-hander Adbert Alzolay (5-13) earned the win out of the bullpen. He pitched 1 2/3 scoreless innings, allowed one hit and struck out two.

Pirates southpaw Sam Howard (2-4) gave up two runs on one hit and one walk in one-third of an inning.

The high-scoring game did not take long for its first display of offense. Tsutsugo hit a one-out homer to center field in the top of the first to give the Pirates a 1-0 lead.

The Cubs took a 2-1 lead in the second on back-to-back homers by Duffy and Heyward.

In the third, Reynolds belted a grand slam to give the Pirates a 5-2 advantage. It was his 22nd homer of the season and the first of his career with the bases loaded.

Chicago answered with a five-run third to go on top 7-5. Ian Happ hit an RBI single, and after the Cubs loaded the bases, Duffy delivered with a grand slam to left. Like Reynolds, it was the first of his career.

The Pirates pulled even at 7 in the fifth. Jacob Stallings hit a sacrifice fly, and Ben Gamel later scored from third base on a wild pitch by Cubs right-hander Manuel Rodriguez.

Stallings notched another RBI on an infield single in the sixth to make it 8-7 in favor of Pittsburgh.

Schwindel played hero in the seventh for the Cubs. His two-out grand slam to center field marked his 11th homer of the season, his 10th since joining Chicago and his third in as many games.

Teammates in the dugout celebrated Schwindel's first career grand slam. He has 10 homers and 29 RBIs in 32 games with the Cubs.

--Field Level Media