Michael Pineda pitched seven strong innings against his former team and was backed by four home runs as the Minnesota Twins defeated the host Seattle Mariners 11-6 on Thursday night in the opener of a four-game series.

Byron Buxton and C.J. Cron hit home runs in a seven-run fourth inning against Mariners right-hander Erik Swanson (1-5). Buxton hit a three-run shot and Cron's homer deep into the second deck in left field scored two as the American League Central-leading Twins took a 9-1 lead.

Jason Castro and Max Kepler hit solo shots in the third inning off Swanson, who gave up eight runs on nine hits in three-plus innings. The rookie didn't walk a batter and struck out three.

Pineda (3-3), a burly right-hander who began his career with the Mariners in 2011 before being traded to the New York Yankees, allowed three runs -- all on solo homers -- on five hits. He struck out six without a walk.

Mallex Smith, recalled earlier in the day from Triple-A Tacoma, J.P. Crawford, Ryon Healy and Daniel Vogelbach homered for the Mariners. It was Crawford's first home run for Seattle after making his debut for the Mariners last Friday.

Smith's homer in the bottom of the third cut Minnesota's lead to 2-1.

But Swanson failed to record an out in the fourth before being relieved. Eddie Rosario led off with a line-drive single to right field and Cron then hit a 1-0 pitch deep to left. Marwin Gonzalez singled and Miguel Sano, making his season debut, doubled to left. Gonzalez scored as Castro reached on Seattle first baseman Edwin Encarnacion's throwing error. Buxton then homered to center on a 2-1 pitch, making it 8-1.

The Twins added one more unearned run in the inning off right-hander Parker Markel as Smith dropped a ball in center field.

Healy and Crawford hit back-to-back homers in the fifth to pull the Mariners within 9-3.

Jorge Polanco's run-scoring single in the eighth gave the Twins a 10-3 lead before Vogelbach hit a three-run homer in the bottom of the inning.

Sano capped the scoring with an RBI double in the ninth.

--Field Level Media