The 2025 American League Championship Series matchup is set!
Starting Sunday in Toronto, the No. 2 seed Seattle Mariners and No. 1 seed Toronto Blue Jays will clash with a trip to the World Series on the line.
Seattle outlasted the Detroit Tigers in a thrilling ALDS Game 5 on Friday night, two days after Toronto dispatched the AL East rival New York Yankees to get to the ALCS.
What has stood out about both teams so far? What does each side need to do to punch a ticket to the Fall Classic? And who are the X factors on each roster? Our ESPN MLB experts break it all down.
Note: Matchup odds come from Doolittle's formula using power ratings as the basis for 10,000 simulations to determine the most likely outcomes. Team temperatures are based on Bill James' formula for determining how "hot" or "cold" a team is at any given point; average is 72.
Toronto Blue Jays vs. Seattle Mariners
At last! Super-fans of 1977 expansion have been waiting for this LCS matchup since the early days of the Carter administration. The Blue Jays and Mariners came into existence at the same time but have never met with stakes like this in play. The M's beat the Jays in a wild-card round matchup in 2022, but this is different.
The two strongest division champs in the AL are vying to end long World Series droughts. Toronto hasn't won the title in 31 years, and Seattle has never won it.
The great Willie Horton was among the first players to play for both franchises. Even though he's best remembered as a Tiger and has a statue outside of Comerica Park, they should still let him throw out the first pitch in Seattle and Toronto. -- Bradford Doolittle
No. 1 seed Blue Jays' concern level: Appropriately alert. Toronto has the better seed and home-field edge, but Seattle has been playing a tick better in the latter stages of the season, and the run differentials are virtually the same.
What's really exciting is the star power on both teams and that the standouts have been shining in October. Julio Rodriguez, Cal Raleigh and the scorching Vladimir Guerrero Jr. have played huge roles in the teams getting this far.
Both teams have leaned on the long ball for scoring, getting more than half their runs on homers. It's a really close matchup that could be decided by Andres Munoz, Seattle's edge at the back of the bullpen. -- Doolittle
Toronto Blue Jays
Odds of advancing: 55.1%
Team temperature: 96
What stood out most as the Blue Jays rolled past the Yankees in the ALDS?
Castillo: The relentlessness of their lineup. Vladimir Guerrero Jr. starred from start to finish, but Toronto received contributions from seemingly everyone manager John Schneider put in there. Four players not named Guerrero recorded two hits in Game 1. Daulton Varsho had four extra-base hits, and Ernie Clement went 3-for-4 in Game 2. Clement added another four hits in Game 3.
The Blue Jays were the toughest team to strike out during the regular season, and they registered more home runs than strikeouts in the first two games at Rogers Centre, where they've thrived all season. It helped that Playoff Vladdy Jr. surfaced, going 9-for-17 with three home runs, including a monumental grand slam in Game 2.
Schoenfield: Have to go with Trey Yesavage's absolutely dominant performance in Game 2, when he made his fourth career start and held the Yankees hitless for 5 innings while striking out 11. The Yankees had no chance against him. Other than the length of the start -- the Blue Jays pulled him with a big lead -- it was as dominant a postseason outing as we've seen in a long time.
His over-the-top delivery creates an unusual look for batters, and he's throwing 95-96 mph with a slider and wipeout splitter. Hard to believe there were 19 players selected ahead of him in the draft in 2024.
Why will (or won't) it work against the Mariners in the ALCS?
Castillo: It'll work at Rogers Centre because it has always worked at Rogers Centre this season. The Blue Jays scored 431 runs at home during the regular season, the third most in the majors. In the ALDS, they scored 23 in two games in Toronto. The Blue Jays dominate pitchers north of the border. The question is whether it'll work in Seattle. T-Mobile Park is a difficult place to hit. Mariners pitchers posted a 3.28 ERA at home this season. But the Blue Jays scored 21 runs in a three-game sweep of the Mariners in May. Maybe their offense will travel.
Schoenfield: It will ... if he throws strikes. He did against the Yankees, walking just one batter in his start, but in the minors, he walked 41 batters in 98 innings. The Mariners have a mix of patient hitters (Cal Raleigh, Randy Arozarena) and hitters who chase (Julio Rodriguez, Eugenio Suarez), but like the Yankees, the Mariners also whiff a lot.
Which one player is the X factor who can make (or break) Toronto's World Series hopes?
Castillo: Trey Yesavage. Asking a rookie with four major league starts to continue dominating deep into October is a lot, but the Blue Jays lack that clear premier ace. Yesavage has the potential to supply it. Not only is his stuff good enough, he's different enough to flummox even the most experienced hitters. His release point and arm angle are among the highest in baseball, making his fastball-splitter combination especially difficult to solve. Then, there's his slider, which often runs arm side instead of the usual glove side. Toronto has been careful with the 22-year-old right-hander. He hasn't thrown more than 94 pitches in a game this season, which started for him in Low-A. Now, he's on the sport's grandest stage and could be the difference in October.
Schoenfield: Shane Bieber. Kevin Gausman and Yesavage looked great, but given a 6-1 lead in Game 3, Bieber got knocked out in the third inning. Given how poorly Toronto's bullpen pitched after that, maybe it was a bit of a quick hook, but it's clear the Blue Jays will need all three of these starters to pitch well, given the bullpen didn't post a bunch of zeroes against the Yankees. The Blue Jays' ability to put the ball in play -- they had the lowest strikeout rate in the majors -- means they should continue to score some runs, so the question is whether they can keep enough runs off the scoreboard.
Seattle Mariners
Odds of advancing: 44.9%
Team temperature: 89
What stood out most as the Mariners beat the Tigers in the ALDS?
Gonzalez: The effectiveness of the starting rotation, which should come as no surprise. George Kirby, Luis Castillo, Logan Gilbert and Bryce Miller -- before the fifth inning, at least -- all pitched well in the ALDS. The hope is that Bryan Woo, the Mariners' best starter this season, will return from a pectoral injury for the ALCS, taking this rotation to yet another level.
The Mariners feel really good about their back-end relievers and believe this is the deepest lineup they've fielded in this era. But this team still revolves around its starting pitching -- a unit that dominated throughout 2024 and finally started to round into form again in the stretch run of this season. The starters need to consistently provide six and seven innings so that manager Dan Wilson doesn't have to venture outside of Gabe Speier, Matt Brash and Andres Munoz late in games. That's the formula.
Doolittle: Seattle's lineup depth is really impressive, even without a standout designated hitter. It's eye-popping to see Eugenio Suarez hitting in the six-hole and J.P. Crawford at No. 9. It's a group that hits for power, steals bases and strikes out at a much less problematic rate than the Mariners lineups we're used to. Raleigh and Rodriguez make for such a dynamic one-two stack in the batting. The R&R Boys.
Why will (or won't) it work against the Blue Jays in the ALCS?
Gonzalez: No team struck out less often than the Blue Jays this season. Only the Yankees and Dodgers finished with a higher OPS. And when the playoffs arrived, Vladimir Guerrero Jr., Ernie Clement and Daulton Varsho slugged a combined 1.000 in four ALDS games. This offense operates at a different level than the Tigers' -- and could have Bo Bichette back for this next round.
Gilbert and Woo pitched pretty well against the Blue Jays this season (five earned runs in 11 2/3 innings). Castillo and Miller (15 earned runs in 15 innings) did not. But these two teams have not seen each other since May. The Mariners' rotation is not the same as it was then.
Doolittle: A deep lineup plays against anybody, but there's one factor that works in Seattle's favor. With Trey Yesavage emerging for Toronto, the Blue Jays have four key hurlers who can dominate with splitters, the breakout pitch of the 2025 postseason. (Yesavage, Kevin Gausman, Seranthony Dominguez and Jeff Hoffman are the four.)
The Mariners were in the middle of the pack in hitting splitters during the season, but they had two hitters who crushed them. And it's the R&R Boys -- Raleigh had 1.159 OPS against splitters and Rodriguez 1.091.
Which one player is the X factor who can make (or break) Seattle's World Series hopes?
Gonzalez: Randy Arozarena. The Mariners inserted Arozarena at the top of the lineup after they acquired Eugenio Suarez and Josh Naylor at the trade deadline, and Arozarena has struggled mightily ever since. He showed some flashes in the ALDS, but the Mariners need "Playoff Randy" -- the one who took over during the 2020 postseason and became a sensation while playing for Team Mexico in the 2023 World Baseball Classic. If he gets going ahead of Cal Raleigh and Julio Rodriguez, the Mariners' offense will be scary.
Doolittle: Matt Brash. Well, that's not fair, as Brash is good, and I picked his name as an avatar for Seattle's middle relief crew. If the Mariners' roster has a soft underbelly, it's the non-closing part of the bullpen. It's not a bad group, but with a deep, productive lineup and a star closer in Munoz, plus excellent starting pitching, it might well be Brash, Eduard Bazardo, Gabe Speier and Carlos Vargas who determine if the Mariners can finally play in a World Series.
