Jorge Polanco went 3-for-3 and hit a tiebreaking two-run homer with one out in the bottom of the eighth inning as the Seattle Mariners defeated the visiting Athletics 4-2 in the season opener Thursday night.

Randy Arozarena also went deep for the Mariners and Tyler Soderstrom hit a pair of solo homers for the Athletics.

Soderstrom led off the eighth inning by lining the second pitch he saw from reliever Trent Thornton just over the right field wall to give the A's a 2-1 lead.

The Mariners tied it with one out in the bottom of the inning on Arozarena's solo shot off the facade of the second deck in left field against Jose Leclerc. Following a walk to Luke Raley, Polanco deposited Leclerc's fastball over the wall in center field to give Seattle its first lead.

Thornton got the victory and Andres Munoz worked the ninth for the save.

For the most part, the opener was a pitching duel between right-handers Luis Severino and Logan Gilbert.

Severino spent the first nine seasons of his career in New York -- eight with the Yankees and last year with the Mets -- before signing with the A's in the offseason. On Thursday, he threw six scoreless innings and allowed three hits, walked four and struck out six.

Soderstrom broke a scoreless tie with one out in the fifth inning, hammering a hanging slider from Gilbert 432 feet over the fence in straightaway center field.

That was the lone mistake by Gilbert, who was making his first Opening Day start. The right-hander allowed just two hits over seven innings, with no walks and eight strikeouts.

The Mariners put runners on base in each of the first six innings against Severino but weren't able to convert.

They finally broke through against reliever Tyler Ferguson in the seventh, tying the score without the benefit of a base hit.

Ryan Bliss and J.P. Crawford led off with walks and Victor Robles squared around to bunt. Robles missed the ball, as did A's catcher Shea Langeliers, with the ball rolling to the backstop.

Bliss tried to score from second and was originally ruled safe, but a video review determined his lead foot bounced off the dirt and didn't touch the plate while Ferguson applied the tag. Crawford took third on the play and scored on Robles' sacrifice fly to center.

--Field Level Media