The Mariners changed the vibe on the second pitch of the day and didn't let up in an 8-1 rout of the Blue Jays.
Canadian Michael Saunders led off with a home run and Dustin Ackley hit his first career grand slam in the fourth inning. Saunders added another solo homer in the fifth as Seattle stretched its winning streak to three games.
The defeat was the latest in a string of uninspired efforts by the 10-21 Blue Jays.
They are mired in a four-game skid, have yet to win a series at home this year and sit 28th out of 30 teams in the overall standings.
"We're all pretty beat up mentally right now," said manager John Gibbons. "But you've got to get through that. It's professional baseball, there's a lot of season left. You get tested and you find out what you're made of. That's basically what it comes down to.
"There's no question, there's talent in the room. It's just what are we going to do with it."
The Blue Jays did not take advantage of the few opportunities they had against Seattle starter Hisashi Iwakuma (3-1), who allowed five hits and one earned run over seven innings.
Toronto loaded the bases with one out in the first inning but couldn't bring a run home. The Blue Jays managed just six hits on the day and finally ended a 23-inning scoring drought with a run in the seventh.
The scoring play generated a stiff round of mocking applause from the crowd, who peppered the Jays with boos throughout the game and broke into the occasional chant of "Go Leafs Go."
"I did hear them, it was hard not to," Toronto knuckleballer R.A. Dickey said of the fans' boos. "They were pretty animated. You can't blame them. We've played well below our expectation. We're booing ourselves. It's tough. We're trying to hang onto the hope that we're too good of a ball club for this to continue.
"It's one thing to say it but we've got to be actively pursuing ways for us to get better."
Ackley broke the game open in the fourth inning when he belted a 3-2 pitch from Dickey over the wall in right-centre field.
"I just said, 'He's going to throw a strike, he's not going to try to walk me,'" Ackley said. "I just told myself to let it get as deep as I could and try to put a put a good swing on it. When I hit it, it was kind of disbelief at first that I hit it as well as I did.”
The homer provided more than enough support for Iwakuma, who trimmed his sparkling earned-run average to 1.61. The Mariners (15-17) had eight hits on the day and have won six of their last seven games.
The Blue Jays have now dropped five series at home this year and split the other. They will try to avoid the three-game sweep in the series finale Sunday.
Dickey (2-5) pitched six innings, allowing six hits, seven earned runs and two walks. He struck out five and his ERA rose to 5.36 from 4.50.
He said he felt fine physically and was not bothered by the neck and back soreness that troubled him over his last few starts.
However, he did raise a few eyebrows when the word "dysfunctional" came up as he discussed the team's slump in his post-game media availability. Dickey later clarified what he meant by the term.
"Dysfunctional in the sense of baseball team, on the baseball field," he said. "Not because guys are fighting in here or bickering or second-guessing each other, because I don't feel that."
Dickey, who won the National League Cy Young Award last year with the New York Mets, retired nine straight after the leadoff homer. But he got into trouble in the fourth inning.
Kendrys Morales hit a one-out single and moved to second on a Michael Morse grounder. Raul Ibanez and Kelly Shoppach drew walks to load the bases before Ackley launched his first homer of the year.
Seattle added another run in the sixth. Ibanez tripled and scored when Shoppach doubled down the left-field line.
The Blue Jays finally got on the board in the seventh when Rajai Davis walked, moved to third on a Henry Blanco double and scored when Munenori Kawasaki hit a sacrifice fly.
Saunders, from Victoria, struck again in the eighth inning with an RBI double off reliever Brett Cecil that scored Robert Andino.
The Blue Jays have lost 10 of their last 12 games. The game took two hours 28 minutes to play.
Notes: Right-hander Brandon Morrow (0-2) is scheduled to start for Toronto on Sunday afternoon. Seattle will counter with left-hander Joe Saunders (2-3). ... The Blue Jays will open a four-game road series at Tampa Bay on Monday. The Mariners will get the day off before continuing their road trip with a two-game set against Pittsburgh. ... Toronto outrighted right-hander Justin Germano to triple-A Buffalo on Saturday, a day after he was designated for assignment. He allowed two earned runs over two innings in his lone appearance with the Blue Jays this season.Suggest a correction