Toronto's bats came alive in the bottom of the second inning. Addison Barger and Isiah Kiner-Falefa each hit an RBI single to give the Jays a 2-0 lead.
In the third inning, Bargers was already up to bat again after Toronto and launched his third home run of the postseason to double the lead to 4-0.
Seattle had bases loaded in the third and fourth innings, both ended on double-plays, failing to score a single run.
Toronto then forced a third straight double play to end the fifth inning as rookie starting pitcher Trey Yesavage finished five straight shutout innings.
The Blue Jays wouldn't stop scoring runs off of Mariners starter Logan Gilbert, who was done after giving up four earned runs (five total runs) on seven hits across four innings of work.
He gave up just one walk and struck out three before delivering a home run to Vladimir Guerrero Jr., who set a franchise postseason record with six home runs in 10 games.
Yesavage's night would come to an end in the sixth inning after giving up a solo home run to Josh Naylor, followed by a two-out single from Randy Arozarena.
Louis Varland came in for Yesavage, who finished with six hits, three walks, and six strikeouts. He would be clocked for a second, and final, earned run after Varland gave up an RBI single to Eugenio Suarez.
Vladdy would find his way back to home plate in the bottom of the seventh inning. After being hit by a pitch, Vladdy would reach second on an Alejandro Kirk single.
The Jays' star would steal third base, but thanks to a wild throw by Mariners pitcher Cal Raleigh, he would take home as well to give his team the 6-2 lead.
Toronto would load up the bases in the same inning, but failed to pour on any further damage en route to their Game 6 win.
The Blue Jays finished with 11 hits, going 3-for-11 with runners in scoring position. Seattle finished with seven hits, going 0-for-2 RISP.
Naylor and Arozarena led the Mariners with two hits each while the rest of the team put up three hits.
Four players would finish with at least two hits for the Blue Jays, including Nathan Lukes, Vladdy, Ernie Clement, and Barger.
Seven of their ten total hitters from Game 6 recorded at least one hit.
Game 7 of the ALCS between the Blue Jays and Mariners will take place on Monday, October 20th, at 8:10 p.m. Eastern (02:10 CET the next day).
The winner will go on to face the Los Angeles Dodgers in the World Series, who are coming off a four-game sweep of the No. 1-seeded Milwaukee Brewers.