Mariners vs. Tigers Prediction, Odds, Probable Pitchers and Prop Bets for ALDS Game 4

Betting odds, pick and prediction for the Seattle Mariners-Detroit Tigers matchup in Game 4 of the ALDS.

Detroit Tigers pitcher Casey Mize is a solid prop target in Game 4 of the ALDS. / Junfu Han / USA TODAY NETWORK via Imagn Images

The Seattle Mariners have a chance to close out their series with the Detroit Tigers in the ALDS on Wednesday afternoon.

Seattle won Game 3 on Tuesday 8-4 behind home runs from Cal Raleigh and Eugenio Suarez. The Mariners were able to jump on starting pitcher Jack Flaherty in that game, but they may not have the advantage on the mound in Game 4.

All-Star Casey Mize is on the bump for the Tigers for the second time this postseason after he tossed three innings of one-run ball in the wild card round against the Cleveland Guardians.

Mize finished the regular season with a 3.87 ERA, and he’s been much better than Seattle’s starter in this game – righty Bryce Miller (5.68 ERA). 

Still, the Mariners’ offense finally was able to get going in Game 3, and that could be a bad sign for a Detroit team that has scored four or fewer runs in five of its six games this postseason.

Here’s a breakdown of the odds, probable pitchers, my favorite prop and a prediction for Game 4 on Wednesday. 

Mariners vs. Tigers Odds, Spread and Total

Odds via DraftKings Sportsbook

Spread

• Mariners -1.5 (+150)
• Tigers +1.5 (-184)

Moneyline

• Mariners: -108
• Tigers: -112

Total

• 8.5 (Over -106/Under -115)

Mariners vs. Tigers Probable Pitchers

• Seattle: Bryce Miller (4-6, 5.68 ERA)
• Detroit: Casey Mize (14-6, 3.87 ERA, 0-0, 3.00 ERA)

Mariners vs. Tigers How to Watch

• Date: Wednesday, Oct. 8
• Time: 3:08 p.m. EST
• Venue: Comerica Park
• How to Watch (TV): FS1
• Series: Mariners lead 2-1

Mariners vs. Tigers Best MLB Prop Bets

Tigers Best MLB Prop Bet

• Casey Mize UNDER 0.5 Walks Allowed (+130)

This season, Mize ranks in the 87th percentile in walk percentage, per Statcast, and he’s only allowed 36 total walks in 139 innings of work. 

In fact, Mize didn’t allow a free pass in three of his five September starts and nine of his outings this season. Since he only threw three innings in the wild card round, there’s a chance that we see Mize lifted early in this matchup as well.

At plus money, this prop is worth a look for the Tigers All-Star on Wednesday. 

Mariners vs. Tigers Prediction and Pick

The Mariners shot up to second in the odds to win the World Series after taking Game 3, but I think this series is going the distance. 

While Mize didn’t pitch well right out of the All-Star break, he did turn in a strong September, posting a 3.49 ERA across five starts, striking out 32 batters in 28.1 innings of work. He may have a short leash in this game, but Detroit has a solid 3.70 bullpen ERA in the postseason. 

Meanwhile, Miller has not pitched well at any point in the 2025 season, and the Mariners may be better off pulling him at the first sign of trouble. 

According to Statcast, Miller ranked in the ninth percentile in expected ERA (5.29) and the seventh percentile in expected batting average against (.285) during the 2025 season. He also ranked in the second percentile amongst MLB pitchers in hard-hit percentage.

If there was ever a game for the Detroit offense to get going, it’s this one.

The Tigers were 11 games over .500 at home this season while Seattle was three games under .500 on the road.

Even after the Mariners took control of the series on Tuesday, I think Detroit bounces back to force a winner-take-all Game 5.  

Pick: Tigers Moneyline (-112 at DraftKings)

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Odds refresh periodically and are subject to change.

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