Adley Rutschman homered in his return to the Pacific Northwest as the Baltimore Orioles defeated the host Seattle Mariners 9-2 Monday night in the opener of a three-game series.

Ryan Mountcastle, Anthony Santander, Austin Hays and Jorge Mateo also went deep for the Orioles, who won for the fifth time in their past six games.

Cal Raleigh homered for the Mariners, who lost their second in a row following a five-game winning streak.

Baltimore right-hander Tyler Wells (6-4) won his fourth straight start. Wells allowed only one hit over five innings, a solo shot by Raleigh with two outs in the fifth. Wells didn't walk a batter and struck out three.

Mariners rookie right-hander George Kirby (2-3), who earned his first major league victory with six scoreless innings against the Orioles on May 31 at Camden Yards, struggled this time, allowing four home runs. Kirby gave up seven runs on nine hits in four innings, with one walk and two strikeouts.

Seattle starters had a franchise-record streak of 24 consecutive games allowing three or fewer earned runs snapped.

The Orioles scored in each of the first four innings.

Trey Mancini doubled with one out in the first, took third on a groundout and scored on Rutschman's two-out infield single.

In the second, Jonathan Arauz singled with one out and scored on Cedric Mullins' two-out double to center.

Baltimore hit back-to-back homers in each of the third and fourth innings.

Rutschman and Mountcastle hit two-out shots in the third to make it 4-0. Santander hit a two-run shot with two outs in the fourth following a Mullins walk and Hays lined the next pitch over the wall in left-center for a 7-0 lead.

After Raleigh pulled the Mariners within 7-1, Mateo went deep off reliever Penn Murfee leading off the sixth.

The Mariners scored in the bottom of the inning as Julio Rodriguez lined a two-out single to left, took second on a walk to Jesse Winker and scored on Eugenio Suarez's double to left.

The Orioles capped the scoring in the ninth as Mullins led off with a double, took third on a Suarez throwing error and scored on Santander's sacrifice fly.