MLB betting preview (Oct. 15): Blue Jays vs. Mariners Game 3 ALCS predictions
Seattle Mariners starting pitcher George Kirby (68) reacts after striking out the side against the Detroit Tigers in the fifth inning during game five of the ALDS round for the 2025 MLB playoffs at T-Mobile Park.
Photo credit: Steven Bisig-Imagn Images
Nicholas Martin
Oct 15, 2025, 13:00 EDTUpdated: Oct 15, 2025, 16:12 EDT
The Toronto Blue Jays face quite a daunting task entering Game 3 of the ALCS, as they will attempt to become the first team since the 1996 New York Yankees to win a seven-game postseason series after dropping the first two matchups at home. To make matters worse, Toronto had arguably the two most favourable pitching matchups it will have in the series in Games 1 and 2.
The Blue Jays are priced at +110 to earn a desperately needed win in Game 3, as Shane Bieber will face off against George Kirby.
One small cause for optimism is that the Blue Jays have performed quite well as underdogs this season. Toronto has won 44 of 77 (57.4%) of games in which it was a betting underdog this season.
Let’s dive into the game odds for Wednesday’s ALCS Game 3 matchup between the Blue Jays and Mariners, courtesy of bet365.

Blue Jays vs. Mariners Game 3 ALCS odds

Blue Jays moneyline odds
+110
Mariners moneyline odds
-130
Runline odds
Blue Jays +1.5 (-210), Mariners -1.5 (+170)
Game total
Over 7 runs (-115), Under 7 (-105)
Date/time
Oct. 15, 8:08 p.m. ET

Betting Toronto Blue Jays

After the Yankees’ elimination in the ALDS, there was plenty of talk in the baseball world regarding whether their one-dimensional, home-run-driven offensive approach could ever lead to meaningful results in the postseason, with the general belief that Toronto’s offensive process is much more stable.
Two games into the ALCS, and now the commentary all revolves around what the Blue Jays are doing wrong offensively. The reality is that baseball is very random, and in a small sample any offensive approach is capable of coming up relatively fruitless.
While I’m not going to try and argue that the Blue Jays have hit the Mariners’ high-quality pitching staff as effectively as they did the Yankees, they have had some awful luck on balls in play in this series and may not need to change all that much to achieve better results.
The Blue Jays have struck out just 13% of the time in this series. A middle-of-the-pack strikeout rate this season was 22%. The quality of Toronto’s contact also appears respectable, as it holds an expected batting average of .241 but a BABIP of .137.
Vladimir Guerrero Jr., in particular, has suffered from some tough luck on well-hit balls in this series, which has been a key reason for his disappointing production after terrorizing the Yankees. He’s gone 0-for-7 in the first two games of the series, but five of those seven outs were hit at 95 mph or harder, including lineouts hit at 107 mph, 107.2 mph, and 109 mph.
The Blue Jays led MLB with an xBA of .269 this season. After having favourable luck on balls in play versus New York, they have had awful luck on balls in play versus the Mariners, and suddenly after two games the entire offensive process is in question.
Dating back to July 1st, the Blue Jays rank first in MLB with a wRC+ of 126 versus right-handed pitching. They rank first in batting average in that span and have struck out just 17.1% of the time. It may not be enough to win if Bieber and the bullpen can’t hold up in this matchup, but it’s realistic to think that the Blue Jays can hit a tough righty in Kirby well in this matchup.
Since starting the season with a highly impressive pair of outings versus the Miami Marlins and Milwaukee Brewers, Bieber’s results have slowly trended in the wrong direction. He entered the postseason with a 4.58 xERA and 3.35 xFIP, and his velocity is down 1.5 mph compared to earlier on in his career, while his Stuff+ rating is down to 92.
John Schneider has drawn plenty of criticism for his decisions to take Kevin Gausman and Trey Yesavage out early in the first two games of this series, and I’m in agreement that those two decisions were quite iffy.
Taking Bieber out in the third inning in Game 3 of the ALDS seems much more reasonable. Bieber allowed five hits in just 2 2/3 innings of work, allowed a hard-hit rate of 51%, and had an expected batting average of .279. Of the 12 balls the Yankees put in play versus Bieber, eight were hit 100 mph or harder.
Pitching at the extremely pitcher-friendly T-Mobile Park could agree with Bieber, though, who has allowed 1.79 HR/9 this season. Per Statcast, T-Mobile ranks as the least favourable ballpark for run creation over the last three seasons, and first pitch calls for 59-degree temperatures.

Betting Seattle Mariners

After a late start to the season after suffering shoulder inflammation in spring training, Kirby was slightly more hittable this season than he was in the first three seasons of his excellent career. Kirby finished with a 4.21 ERA and allowed a batting average of .252.
In his final 10 regular season appearances, Kirby pitched to an ERA of 4.33 but held strong underlying results, including a 2.95 xFIP and a strikeout-minus-walk rate of 22.6%. He was hard-hit just 28.8% of the time but did allow a line-drive rate of 25.2%. His pitch metrics were down relative to his career average in that span, as he held a Stuff+ rating of 99.
Kirby was very effective in the ALDS versus the Detroit Tigers, finishing with an ERA of 2.70 and racking up 12.60 strikeouts per nine in 10 innings of work.
While Kirby’s results versus the Tigers are intimidating, the Blue Jays offer a drastically more difficult test. Since the All-Star break, Detroit ranked 27th with a wRC+ of 86 versus right-handed pitching and held the third-worst BB/K ratio in baseball.
Winning Game 2 in blowout fashion allowed manager Dan Wilson to save his best bullpen arms for tonight’s matchup, if needed, and after an off-day Tuesday, Seattle’s elite relievers are in good shape.
While the Blue Jays have gotten the least out of a respectable offensive process in the first two games of the series, the Mariners have done well to come through with a number of timely hits to mask their 31% strikeout rate. Seattle also holds an xBA of .227 but a BABIP of .310.

Predictions for Blue Jays vs. Mariners Game 3

As Bieber has looked fairly shaky of late and the Blue Jays bullpen feels entirely unconvincing, it’s hard to see much value in backing Toronto to win this game, even if it could be due for a better offensive performance based on a respectable process in Games 1 and 2.
The Blue Jays have been the best offence in baseball versus right-handed pitching since August 1st, and I’m not a believer that their performances in Games 1 and 2 should change our viewpoint on the team that significantly. Kirby’s stuff has not been that overpowering this season, and we should see the Jays stick with their usual process, managing plenty of balls in play by keeping strikeouts at a minimum.
Considering the state of the Mariners’ elite bullpen, Kirby likely will only pitch deep into this game if he is completely cruising. Given my belief that the Blue Jays can hit him respectably and the probability that he’s not pushed deep into this game, I see value in backing Kirby to record under 15.5 outs while managing less than five strikeouts at +140.
Best Bet: George Kirby Under 15.5 Outs/Under 4.5 Strikeouts Parlay +140 (bet365, Play to +130)