Our MLB Best Bets takes a look at this Yankees vs. Mariners matchup for Tuesday, July 8.Â
One week out from the MLB All-Star Break, the New York Yankees find themselves in unfamiliar territory — on a slide and losing ground in the AL East. The Bronx Bombers have dropped to 3.5 games behind the first-place Toronto Blue Jays and are currently chasing the surging Seattle Mariners, who also sit 3.5 games ahead in the AL West.
New York enters Tuesday night’s game as a -119 favorite against the Mariners, with the Over/Under set at 9 runs, according to the latest MLB odds. However, while the Yankees may be favored on paper, the smart money in the market is heading the other way.
#Yankees vs. #Mariners pitching probables:
Tuesday: Will Warren (5.02 ERA) vs. Logan Gilbert (3.40 ERA)
Wednesday: Cam Schlittler (MLB debut) vs. Logan Evans (2.96 ERA)
Thursday: Marcus Stroman (7.45 ERA) vs. Bryan Woo (2.77 ERA)— Max Goodman (@MaxTGoodman) July 8, 2025
Sharp Action Driving Mariners Line Movement
Seattle opened as a +110 underdog, but sharp bettors quickly jumped on the value. That professional action — known in betting circles as steam — caused books across the market to adjust the line down to +104, with some sharper books going even shorter.
Steam typically indicates that respected bettors are making large, simultaneous wagers on the same side — in this case, the Mariners — across multiple sportsbooks. It’s a market-wide movement not driven by public sentiment, but by bettors with inside data or powerful models.
How the Teams Have Fared as Favorites and Underdogs
The movement aligns with how these teams have performed in similar betting spots this season:
Yankees as Favorites
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The Yankees have been favored in 80 games, winning 46 of them (57.5% win rate).
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When favored by -132 or more, New York has gone 40-29, a 58% success rate.
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Tuesday’s -119 line implies a 56.9% chance of winning.
Yesterday was not the first time Bellinger saved the day this season pic.twitter.com/3iaf3FqljV
— YankeesMuse (@YankeesMuse) July 7, 2025
Mariners as Underdogs
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Seattle has been underdogs in 30 games and won 14 of them (46.7% win rate).
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When listed as a +112 or longer underdog, they are 8-7, good for a 53.3% win rate.
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Tuesday’s odds imply a 47.2% chance of a Mariners victory.
The takeaway? The Mariners have outperformed in similar underdog roles, while the Yankees have been somewhat average in mid-tier favorite spots like tonight.
Why the Pros Are Leaning Seattle
There are three major reasons the sharps are fading New York:
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Form & Matchups: The Yankees have been inconsistent both on the mound and at the plate lately. Seattle, meanwhile, is riding improved pitching and timely hitting.
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Line Value: Getting the Mariners around +104 or better is appealing given their recent trends and New York’s vulnerability.
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Market Overcorrection: Public perception tends to skew heavily toward big-market teams like the Yankees. Sharp money takes advantage of inflated lines created by public overbetting.
Total Insight: Over 9 Lean
While most of the professional action has hit the moneyline, the total of 9 runs is drawing attention as well. Given both teams’ recent bullpen inconsistencies and streaky offenses, there’s a soft lean toward the Over, especially if the lineups include power bats returning to form.
Tuesday’s MLB Best Bets for Yankees vs. Mariners:
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Moneyline: Mariners +104
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Total: Over 9 runs
As always, be sure to shop around for the best number, especially in sharp-backed matchups like this one. The Mariners may not be favorites on the board, but they are tonight in the eyes of the pros.
