Bautista has blasted a team-record 49 homers this season and is on the verge of becoming the 26th player in history to reach the 50-homer mark. Prince Fielder (50) and Alex Rodriguez (54) last reached the milestone in 2007.
The 29-year-old Bautista, who had not hit more than 16 homers in a season before this year, managed two home runs over the weekend in Boston, where the Jays took two of three, but were denied a sweep on Sunday in a 6-0 loss.
Shaun Marcum (12-8) allowed six runs on nine hits in 5 1/3 innings for the Blue Jays, who were shut out for the eighth time this season and fell for the eighth time in their last 11 games overall.
The loss also officially eliminated the Blue Jays from postseason contention.
Getting the call for the Jays tonight will be Marc Rzepczynski, who is 1-4 with a 6.15 ERA. Rzepczynski did not get a decision last Monday in Baltimore, as he allowed a pair of runs and six hits in five innings of a 4-3 loss.
Rzepczynski did not record a decision in his only other start against the Jays, as he gave up three runs and five hits in 5 1/3 innings of that outing last season.
Seattle, meanwhile, comes into tonight's tilt after taking two of three from the Texas Rangers. The Mariners pulled out a series win on Sunday, as Josh Wilson singled home the go-ahead run in the bottom of the seventh inning, lifting Seattle to a 2-1 win.
Doug Fister (6-12) gave up a run on nine hits over seven innings for the Mariners.
Heading to the hill for the Mariners tonight will be lefty Luke French, who is 4-5 with a 4.02 ERA. French did not factor in the decision of his team's 9-6 loss to Boston on Tuesday, allowing four runs and six hits in seven innings.
This will be his first-ever start against the Blue Jays.
Bautista won't be the only one chasing a milestone in this series, as Seattle outfielder Ichiro Suzuki is on the cusp of his 10th consecutive 200 hit season.
Suzuki leads the majors with 193 hits and should he end the year as the league leader in that category it would mark the fifth straight year he has done so and the seventh time overall, which would tie Pete Rose and Ty Cobb for most seasons leading the majors in hits.
The Mariners and Jays split a two-game set at Safeco Field back in May.