ALCS Betting Preview: Seattle Mariners vs Toronto Blue Jays, Picks and Predictions

What a series we have here. Sometimes the better team wins, and I believe that’s what we have here—the two best teams in the American League square off in a seven-game series to win the pennant.

There isn’t much time to rest; the series starts on Sunday, October 12th at 8:03 PM EST. The Mariners will have to get on a plane after a 15-inning marathon from Seattle to Toronto to play the American League’s best home team. It will be a big challenge, but can they overcome it? Let’s break it down.

Seattle Mariners vs Toronto Blue Jays

Odds to Win Series: Mariners (+105), Blue Jays (-125)

The Bax X Projection: Mariners (66.1%), Blue Jays (33.9%)

Season Series: The Blue Jays went 4-2 against the Mariners this season, highlighted by a home sweep at the beginning of May. However, in Seattle, the Mariners took two of three in April.

Offense: These two teams are both in the top ten in wRC+ against both lefties and righties. Two excellent offenses all year, but they have different identities. The Mariners hit the third most home runs in baseball, while the Blue Jays rank 13th.

However, nobody hit for a higher average and struck out less than the Toronto Blue Jays, which is a big reason why they had the highest on-base percentage in baseball. In the division series, the Blue Jays’ offense looked a lot better, but that’s only one series.

Imagine this offense right now with a healthy Bo Bichette. The Blue Jays’ shortstop finished tied for second in MLB in hits this year despite playing in 139 games. Based on reports, it seems likely that he’ll miss this series as well.

The latest update we received is that he was spotted jogging at Yankee Stadium without a knee brace. That’s good news if the Blue Jays get past the Mariners, but expecting him to be available for this series coming up feels wildly ambitious.

The Mariners’ pitching staff found an edge against the Tigers, making them beat you on sliders. They set the record for the highest usage of that pitch in game five, and it worked perfectly.

They’ll have to find a new edge here, as the Blue Jays rank seventh in xwOBA against sliders this season.

Against every off-speed and breaking ball a pitcher could throw, the Blue Jays are the second-best offense by xwOBA. They are the tenth-best team against four-seamers, sinkers, and cutters.

The Yankees got demolished by splitters from Kevin Gausman and Trey Yesavage, and those two should have similar success against Seattle.

The Yankees and Mariners performed similarly against splitters this season, a .262 xwOBA compared to a .258 xwOBA. Seattle had a higher whiff rate against the splitter as well.

Overall, I’m still taking the Blue Jays offense even without Bo Bichette. While the Mariners are more explosive, I prefer the lineup that doesn’t strike out and makes much more contact.

It’s not as if the Blue Jays don’t hit home runs, and they finished with a higher SLG than Seattle did in the regular season.

Starting Pitching: I upgraded the Mariners’ edge in the rotation from a “light” edge to a “strong” edge as it looks like Bryan Woo will be available for this series. He isn’t just a cog in the machine; he’s been the best pitcher in an already elite starting rotation.

Bryce Miller had an up-and-down season, but his playoff performance against Detroit gives Seattle another weapon. Seattle just announced that he’ll get the ball for game one, and while he’s last on the toteum pole for Seattle, he’s still a solid option.

The Blue Jays didn’t carry a true fourth starter on their ALDS roster; it will be a toss-up between Eric Lauer, Chris Bassitt, and Max Scherzer.

Jose Berrios hit the IL with an elbow issue at the end of September, so it’s expected he won’t pitch in the playoffs, especially considering he had one of his worst seasons. While Seattle is much deeper, the Blue Jays have three fantastic options in Kevin Gausman, Shane Bieber, and Trey Yesavage.

The Blue Jays’ rotation has the talent to compete, but the Mariners have the second-best rotation in the playoffs, only behind the Dodgers. It will be a fascinating matchup against an offense like the Blue Jays.

Bullpen: When it comes to the ninth inning, Jeff Hoffman doesn’t compare to Andres Munoz. Munoz has been one of the best relievers in baseball, and against the Tigers, he was lights out.

In the regular season, the Mariners’ bullpen has a slight edge in FIP (3.90 vs 3.99), but the Blue Jays had the better K-BB ratio. However, those numbers don’t mean much in the playoffs, as the regular season often showcases the bullpen’s weakest performances in blowout games.

The Mariners’ lack of left-handers could hurt them if they get to the World Series, but in this matchup, the three best hitters on the Blue Jays are all right-handed (Guerrero Jr, Kirk, and Springer). That doesn’t mean they neutralize those three, but we saw what happened with Kerry Carpenter; Seattle didn’t have an answer.

The two hitters the Blue Jays should have the most trouble with are Cal Raleigh and Jorge Polanco, both of whom are switch-hitters. Julio Rodriguez and Randy Arozarena can break out at any time, but the Blue Jays have plenty of right-handers to combat them.

The reason I give Seattle a slight edge, despite both bullpens being similar in a vacuum, is what we saw in extra innings against Detroit. Because their rotation is so deep, they can deploy a starter in case of an emergency. The Blue Jays don’t really have that luxury.

Defense: This is the most significant edge in the playoffs so far. In terms of Fielding Run Value, the Blue Jays have the best defense in Major League Baseball.

While losing Bichette is a harsh blow to the offense, his defense could have hurt the Blue Jays in tight games. The Mariners have the fifth-worst defense in baseball at -30, only better than the Rays, White Sox, Nationals, and Angels.

This is especially important given the extent of contact the Blue Jays made. The Tigers struck out so much against the Mariners that they couldn’t put their defense to the test.

On the flip side, Seattle will have to earn their way on base. There is such a stark difference here that it could end up tipping the scales in Toronto’s favor.

Baserunning: Neither team is an issue on the bases. The Blue Jays rank 23rd in Baserunning Runs, while the Mariners rank 25th. In terms of runs via extra bases taken, the Mariners rank dead last, but the Blue Jays are still below average. Not much to break down here.

Overall Outlook

This is such a fascinating matchup—two great offenses with different identities and two rotations with plenty of top-end talent. I believe the Mariners have the best roster, but the Blue Jays match up really well against Seattle. They can neutralize the Mariners’ ability to strike out batters, and they’ll make enough contact to really test the below-average Mariners defense.

These two teams were excellent in their home ballparks this year. We saw first-hand how difficult it is to beat Toronto at the Rogers Centre, but on the flip side, the Mariners were uber-dominant at home and beat Tarik Skubal twice at T-Mobile Park.

The Bat X projects a Mariners win 66.1% of the time (implied odds of -195). That’s a massive edge based on my favorite projection system. However, when I break down the matchup, I lean Toronto’s way.

I think it will be difficult for Seattle to win game one. After a 15-inning marathon, they have to travel from Seattle to Toronto. Mariners pitchers threw 209 pitches last night, which is 64 more than an average nine-inning game.

Logan Gilbert and Luis Castillo combined to throw 49 pitches in that game, and while it was Gilbert’s “throw day” in between starts, there is a much bigger difference between a short bullpen session and 34 pitches in a high-stress environment.

This is the first time in MLB history that a team has won in 15 innings and then had to travel for the next series. The only other time a team won a winner-take-all game in extra innings was in 1995, when the Seattle Mariners beat the New York Yankees in 11 innings.

That was a different circumstance, as the Mariners got nearly seven innings from their starter, and then three from Randy Johnson. Funny enough, they won game one of the ALCS against the Cleveland Indians, but ended up losing the series.

This puts Seattle into an even worse spot. They have to face Kevin Gausman on the road on such short notice. However, I don’t think it’s a huge deal; it’s just a slight edge for Toronto. It’s hard to quantify, so I didn’t when I broke down the series by the numbers.

I make the Blue Jays -145 ML favorites in Game 1 with Kevin Gausman opposing Bryce Miller. Based on the current market value, I don’t see any value in taking them to win Game 1. However, there is value in the series price as I expect them to perform well 59.2% of the time.

Teams that win game one of a seven-game series in MLB history at home are 75-35, winning 68.1% of the time. In general, teams that win game one take the series about 65% of the time, but having home-field advantage increases their chances of winning the series.

Using those two percentages to calculate the expected value of this bet, my fair odds are +148.

If you think the Blue Jays have a higher chance of winning game one than I do, you’ll see even more value. If you believe the Mariners will win game one, obviously don’t bet this prop.

If you do show value on the Mariners, take them at +200 to win game one and the series. Teams that win game one on the road go on to win the Championship Series or World Series 59% of the time.

Obviously, a team can lose game one and win the series or vice versa, but the most likely scenario, in my opinion, is the Blue Jays winning game one and going on to win the series.

I didn’t factor in what Seattle had to go through towards my game one price. It “feels” as if it will hurt them, but there is no historical data to make that claim. If they were playing today, I would feel different, but they do get an off-day in between. I do feel it will hurt them throughout the series, but our only evidence for that is the 1995 Mariners losing in six games in the ALCS.

Home-field advantage is huge here for Toronto. They had the best home record in the American League this season at 54-27, while Seattle went 39-42 on the road.

Seattle also has a challenging home environment, and they use it to their advantage, going 51-30, and the Blue Jays fell a game below .500 on the road, going 40-41.

I think the Blue Jays will win the first two games at home, and then the Mariners will take two of three games in Seattle. That gives the Blue Jays a 3-2 lead going into Toronto with two games to go. That’s just a prediction, not based on my model or anything similar.

My model and I both agree that the Blue Jays will win game one and go on to win the series. At +160, this bet is showing an 8% ROI.

If you make the first game moneyline -160, which is the current price in the market, the ROI breaks down to a little over 9%. If you make the moneyline -135, as was the opener, it’s a minimal edge, about a 1.7% ROI.

Beyond the numbers, I love the matchup for Toronto. The ability to wear down starters and make a ton of contact against a suspect defense will show up in this series, and their pitching is good enough to combat the Mariners’ offense.

For all of these reasons, I think the Blue Jays will win game one and win the series. I would take this down to +150.

The Pick: Blue Jays Win Game 1/Win Series (+160) Risk 1 Unit

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