Oct 8, 2025; Bronx, New York, USA; Toronto Blue Jays first baseman Vladimir Guerrero Jr. (27) celebrates on the field after defeating the New York Yankees in game four of the ALDS round of the 2025 MLB playoffs at Yankee Stadium. Brad Penner-Imagn Images

Did the Mariners’ Bullpen Just Give the Blue Jays a Series-Changing Edge?

Originally posted on Toronto Blue Jays on SI
By Jeremy Trottier | Last updated Oct 11, 2025 4:00 PM ET

The Toronto Blue Jays' matchup for the American League Championship Series is set , as they will take on the Seattle Mariners for a shot at their first World Series appearance since back-to-back wins in 1992 and 1993. This should be a tightly contested matchup, as both teams have been competitive throughout the majority of the season and have proven to be the best in the league.

With that said, some smaller components of the game could factor into who walks out victorious, especially if the games are as close as expected. While the Blue Jays were relatively quick to dispatch the New York Yankees, the Mariners took a full five-game series, including a 15-inning last matchup, to turn away the Detroit Tigers.

Game 5 between the Mariners and Tigers took 4 hours and 58 minutes making it the longest winner take all game ever.

What. A. Night. pic.twitter.com/T0NJf31Kj5
— Simply Seattle (@simplyseattle) October 11, 2025

This makes for an intriguing narrative heading into the first game, which takes place tomorrow, October 12, in Toronto, nonetheless. That being the Mariners heading nearly 2500 miles, following a 15-inning game, with a bullpen that will likely be at least somewhat shorthanded, for game one of the series.

The bullpen component is something worth keeping an eye on, given that Seattle utilized six different pitchers following their starter in game five, leaving them a bit behind for their next matchup.

How Many Mariners Relievers Will Be Available With Reasonable Rest?

Joe Nicholson-Imagn Images

The bullpen for Seattle is going to be under a lot of stress in game one of the ALCS, with four of their top options having thrown in the last game. Andrés Muñoz, Matt Brash, Eduard Bazardo and Gabe Speier all threw pitches in the last game, with the three former having thrown at least 25 pitches each. Additionally, starters Logan Gilbert and Luis Castillo also threw in the game, going 2.0 and 1.1 innings, respectively.

So, the arms in the Mariners' bullpen who did not throw in the last game are Caleb Ferguson, Carlos Vargas, Luke Jackson and Emerson Hancock. Vargas and Jackson both threw on October 8 but should be clear by Sunday, though Vargas did go 33 pitches, so he may be reserved for an emergency.

Ultimately, this is going to be a game that relies heavily upon the starting pitchers involved, especially for Seattle, which would really prefer to avoid using much of its bullpen where possible. The good news for them is that they have an exceptional starting rotation; the bad news is the amount of travel they have to do following a game that lasted nearly five hours.