Marcus Semien and Jurickson Profar each went 3 for 4, with Semien hitting a home run and Profar driving in four runs, as the Oakland Athletics defeated the visiting Seattle Mariners 11-2 Saturday night.

Oakland right-hander Frankie Montas (9-2) pitched six quality innings, allowing two runs on six hits with one walk and nine strikeouts.

For the fifth time this season, the Mariners used an "opener" before their primary pitcher. And for the third time, the opener allowed three runs in the first inning.

This time it was right-hander Gerson Bautista (0-1), who lasted just two-thirds of an inning, giving up two hits and walking three while striking out one.

Left-hander Wade LeBlanc, who had allowed just three runs in 14 innings in two previous appearances following an opener, this time was rocked for six runs on eight hits in 2 2/ 3 innings as the A's built a 9-1 lead through four innings.

Bautista walked the first two batters he faced in the first before getting a lineout and strikeout.

Another walk loaded the bases, and Ramon Laureano lined a two-run single to left field. Profar followed with a line drive to left off the glove of Mariners shortstop J.P. Crawford, making it 3-0.

The Mariners scored in the second on a walk, a double by Tim Beckham and a groundout, but Oakland got that run back in the bottom of the inning on Semien's solo shot to left field, his 10th home run of the season.

The A's pulled away with five runs in the fourth.

Josh Phegley led off with a double to left and scored on Semien's single. Matt Chapman's double plated Semien, and Khris Davis grounded a single to center to make it 7-1.

Mark Canha doubled and Laureano reached on an error, one of four by Seattle, to load the bases. Profar then lined a two-run single to left for a 9-1 lead.

The Mariners scored their final run in the fifth on a one-out double by Dylan Moore and Crawford's RBI single with two outs.

The A's capped the scoring in the sixth. With one out, Canha was hit by a pitch and scored when Crawford made a throwing error on a ball hit by Laureano. Profar grounded a run-scoring single to right to make it 11-2.

The Mariners were a player short on the roster after designated hitter Edwin Encarnacion, who leads the American League with 21 home runs, was traded to the New York Yankees. Both teams announced the trade as official late Saturday. The Mariners also were without second baseman Dee Gordon (injured list with soreness in his right wrist).

--Field Level Media