BALTIMORE -- Dylan Bundy befuddled Seattle throughout Tuesday night's game. The Baltimore Orioles starter used all of his pitches, changed speeds, and the Mariners could manage nothing more than one bunt single early in the game.

Bundy threw a complete-game one-hitter and struck out a career-high 12 batters, and Manny Machado led a four-homer attack with two solo shots as the Orioles extended their winning streak to six games with a 4-0 victory over the Mariners.

For the Orioles (67-65), this was the team's 33rd individual one-hitter, 40th overall, and the first by one pitcher since Jason Hammel did it in June 2012 vs. Atlanta.

The 24-year old Bundy (13-8), who came back off the bereavement list for this game, combined with catcher Welington Castillo in mixing pitches and speeds, relying on a good slider plus a strong fastball and changeup and allowed only a fourth-inning bunt single from Kyle Seager.

The Seattle third baseman dropped that bunt against the shift, and Bundy fielded the ball but bobbled it and had no play. But just about everything else went right for Bundy in this game.

"Yeah, I just threw the curveball a couple times, but mainly it was fastball, slider, change back there," Bundy said. "But yeah, I felt good with all of my pitches and location as well."

His work was even more impressive considering the fact that the right-hander lost a family member in recent days and needed to bounce back from that and had to battle through a 32-minute rain delay at the start.

All of that that left manager Buck Showalter truly impressed.

"He flew in late last night and landed about midnight," Showalter said. "Had to work through the rain delay, too. There were a lot of things that could have been a challenge for him and he doesn't let it be, he's so strong mentally. He was outstanding, obviously. That was fun to watch. Especially when you think about everything that was at stake for both clubs."

Bundy retired seven in a row early in the game and, after giving up the Seager single in the fourth, set down the next 12 Mariners until Guillermo Heredia reached on shortstop Tim Beckham's second throwing error of the night.

Bundy struck out at least one batter in eight of his nine innings and struck out the side in the third. He threw 116 pitches, 85 of which were strikes.

Castillo said he knew early that Bundy would have a very good night.

"From the 'pen he had great life on the fastball," Castillo said. "So when he took the mound it was nice and smooth. I just let the flow go. What was working for him? Everything was working. I was just calling the game with the stuff that he had today."

Jonathan Schoop gave the Orioles the lead with his solo homer in the first. Machado (sixth, eighth) and Castillo (seventh) added insurance later.

All four of the Baltimore homers were solo.

Schoop reached a personal milestone in the process. He got his 500th career hit.

Bundy walked two in the third but struck out the side and escaped trouble. He also got out of a jam in the ninth with a runner on third and two outs.

Seattle starter Erasmo Ramirez (5-5) allowed two runs and five hits in six innings. Ramirez turned in a solid effort, but the Mariners could not help him much.

"He threw the ball well all night," Seattle manager Scott Servais said. "Solo home run got us all night. He gave us a chance, but we did nothing offensively."

The Mariners (66-67) have dropped the first two games of this series but also were impressed by what they saw from Bundy.

"This is the best (pitching) I have seen all year," said Seattle's Yonder Alonso.

NOTES: LHP Donnie Hart was optioned back to Triple-A Norfolk to make room on the roster for RHP Dylan Bundy. He was coming off the bereavement list. ... The rain delay was the 17th time the Orioles have experienced a weather delay at home this year. ... Seattle OF Jarrod Dyson worked out some before the game but the day-long rain limited what he can do. He's still not on the active roster although eligible to come off the disabled list this past Sunday.