Seattle Mariners vs Toronto Blue Jays Picks and Predictions October 17th 2025

Toronto Blue Jays vs Seattle Mariners Game 5 Preview

The Toronto Blue Jays and Seattle Mariners square off Friday afternoon in Game 5 of the American League Championship Series with the series tied 2-2. The matchup takes place at T-Mobile Park in Seattle, where the Blue Jays have caught fire with two straight wins.

After a strong start to the series, the Mariners have seen their momentum stall behind an inconsistent offense. Seattle’s manager Dan Wilson announced Bryce Miller will get the start over Bryan Woo, who is returning from a pectoral strain and will move to the bullpen. Miller earned the win in Game 1, holding Toronto to two hits and one run over six innings.

Toronto will counter with Kevin Gausman, who pitched well in Game 1 but took the loss despite allowing just two earned runs. With both teams’ pitching staffs stretched thin, Game 5 could determine who gains control heading back to Canada.

Follow all postseason lines and game updates on the MLB odds page.

Line Movement and Odds

Oddsmakers have this Game 5 nearly even, with Toronto listed at -111 and Seattle at -109. The run total sits at 7.0, reflecting the expected duel between two high-end right-handers. Line movement throughout the day has leaned slightly toward the Mariners at home.

See how the market shifts before first pitch in the MLB picks section.

Matchup Breakdown

The Mariners have been a tale of two teams in the ALCS. Seattle opened the series with two convincing road wins in Toronto before their bats cooled at home. The offense has managed just four runs combined in the last two games, failing to solve Toronto’s pitching depth.

Bryce Miller has been a postseason bright spot, entering with a 2.61 ERA across two playoff starts. His control and poise were evident in Game 1 when he retired 13 of the final 14 batters he faced. The key for Miller will be neutralizing Vladimir Guerrero Jr. and Andrés Giménez, who have powered the Blue Jays’ lineup with timely home runs in back-to-back games.

Seattle’s bullpen remains solid but overworked. Bryan Woo, who was expected to start Game 5, moves into relief duty as he continues building up from injury. Logan Gilbert and Luis Castillo, both recent starters, could be available for limited bullpen roles if the game stays close.

Toronto turns again to Kevin Gausman, who’s been dependable all postseason with a 2.38 ERA in two starts. His splitter has been devastating against right-handed hitters, and his command gives the Blue Jays a clear edge in consistency. Toronto’s lineup has produced 21 runs over the past two games, fueled by Guerrero Jr. and Giménez combining for six RBIs.

For advanced performance stats and postseason pitching data, check the expert baseball betting guide.

Key Storylines

Seattle’s decision to hold Bryan Woo for bullpen use could be pivotal. Woo was dominant all season, going 15-7 with a 2.94 ERA before his injury, but the club is prioritizing long-term recovery over workload risk. Bryce Miller now faces the challenge of shutting down a Toronto offense that has found its rhythm at precisely the wrong time for the Mariners.

For the Blue Jays, health and timing have aligned. Toronto’s pitching depth has been critical, and Gausman’s poise in big games continues to set the tone. Even with outfielder Anthony Santander out for the remainder of the postseason due to a back injury, Toronto’s lineup depth with Joey Loperfido stepping in has softened the blow.

The Mariners, meanwhile, will lean heavily on Cal Raleigh and Julio Rodríguez to drive the offense. Raleigh, who homered off Gausman in Game 1, remains Seattle’s best hope to break through early.

Prediction

Game 5 comes down to momentum and execution. The Blue Jays have found their stride at the plate, while the Mariners have relied on pitching to stay competitive. Gausman’s consistency gives Toronto the edge, but Seattle’s resilience and home crowd make this a near coin flip.

Projected Score: Toronto Blue Jays 4, Seattle Mariners 3
Best Bet: Blue Jays -111
Secondary Lean: Under 7.0 (-107)

Get the latest playoff insights and Game 6 previews at ScoresAndStats MLB Picks.