Orioles 4, Mariners 0: Delmon Young hit a three-run homer and Wei-Yin Chen pitched eight strong innings as visiting Baltimore defeated Seattle in the opener of their four-game series.

Nick Markakis added a run-scoring single for the Orioles, who maintained their three-game lead over the New York Yankees and Toronto Blue Jays in the American League East. The Mariners have lost three straight games and are just 2-5 since play resumed after the All-Star break.

Chen (11-3) scattered five hits and one walk while winning his fourth consecutive start and Darren O’Day worked a perfect ninth. Seattle’s Hisashi Iwakuma (8-5) allowed four runs and seven hits in seven innings but extended his streak of not issuing a walk to 35 2/3 frames.

Ryan Flaherty, Caleb Joseph and Markakis hit consecutive singles off Iwakuma in the third inning to account for Baltimore’s first run. Young followed by smacking the first pitch of his at-bat well over the left-field fence to make it a four-run advantage.

Young and Joseph each had two hits for the Orioles, who improved to 4-3 on their 10-game road trip. Seattle’s James Jones reached third base in the first inning but was thrown out at the plate on Robinson Cano’s grounder as the Mariners were blanked for the 12th time this season.

GAME NOTEBOOK: Seattle acquired 1B-DH Kendrys Morales from Minnesota for RHP Stephen Pryor. Morales, who hit 23 homers for the Mariners in 2013 before departing as a free agent, is expected to join the team Friday. … Baltimore 3B Manny Machado (back) missed his third consecutive contest. … The Mariners placed INF Willie Bloomquist (knee) on the disabled list and recalled 1B-DH Jesus Montero (0-for-3 on Thursday) and SS Chris Taylor (1-for-3) from Triple-A Tacoma.