Mariners vs Red Sox Prediction, Odds, Moneyline, Spread & Over/Under for June 20

Odds updated as of 5:13 a.m.

Saturday's slate in the MLB includes a matchup between the Seattle Mariners and the Boston Red Sox.

Before checking out the MLB betting lines on FanDuel Sportsbook, we've got you covered, in terms of the vital information about this game.

Mariners vs Red Sox Game Info

• Seattle Mariners (39-38) vs. Boston Red Sox (30-43)
• Date: Saturday, June 20, 2026
• Time: 10:10 p.m. ET
• Venue: T-Mobile Park -- Seattle, Washington
• Coverage: Mariners.TV and NESN

Mariners vs Red Sox Odds & Moneyline

• All MLB odds, betting lines and prop bets are available on FanDuel Sportsbook.
• Moneyline: SEA: (-126) | BOS: (+108)
• Spread: SEA: -1.5 (+180) | BOS: +1.5 (-220)
• Total: 7.5 -- Over: (-104) | Under: (-118)

Mariners vs Red Sox Probable Starting Pitchers

Probable Pitchers: Emerson Hancock (Mariners) - 5-3, 3.28 ERA vs Connelly Early (Red Sox) - 5-5, 3.81 ERA

The probable starters are Emerson Hancock (5-3) for the Mariners and Connelly Early (5-5) for the Red Sox. Hancock's team is 5-9-0 against the spread in his starts this season. When Hancock starts a game and his team is the favorite on the moneyline, they have a record of 7-5. The Red Sox have gone 5-9-0 against the spread when Early starts. The Red Sox are 2-1 in Early's three starts this season that they were the moneyline underdog.

Mariners vs Red Sox Prediction & Pick

All MLB win probability predictions and picks are according to numberFire.
Prediction: Mariners win (60.8%)

Mariners vs Red Sox Moneyline

• Boston is the underdog, +108 on the moneyline, while Seattle is a -126 favorite at home.

Mariners vs Red Sox Spread

• The Red Sox are at +1.5 on the runline against the Mariners. The Red Sox are -220 to cover the spread, and the Mariners are +180.

Mariners vs Red Sox Over/Under

• The over/under for Mariners-Red Sox on June 20 is 7.5. The over is -104, and the under is -118.

Bet on Seattle Mariners vs. Boston Red Sox on FanDuel today!

Mariners vs Red Sox Betting Trends

• The Mariners have been victorious in 36, or 52.2%, of the 69 contests they have been chosen as favorites in this season.
• This season Seattle has come away with a win 30 times in 53 chances when named as a favorite of at least -126 on the moneyline.
• The Mariners' games have gone over the total in 37 of their 76 opportunities.
• In 76 games with a line this season, the Mariners have a mark of 28-48-0 against the spread.
• The Red Sox have won 38.5% of the games this season they were the underdog on the moneyline (10-16).
• In games it has played as a moneyline underdog with odds of +108 or longer, Boston has a 5-10 record (winning only 33.3% of its games).
• The Red Sox have combined with opponents to hit the over on the total 33 times this season for a 33-38-2 record against the over/under.
• The Red Sox have covered 41.1% of their games this season, going 30-43-0 ATS.

Mariners Player Leaders

• Julio Rodriguez leads Seattle with a slugging percentage of .436, fueled by 29 extra-base hits. He has a .249 batting average and an on-base percentage of .309.
• Among qualifying hitters, he is 83rd in batting average, his on-base percentage ranks 117th, and he is 71st in slugging.
• Rodriguez has picked up at least one hit in three games in a row. In his last five games he is batting .158 with a double, a home run, a walk and three RBIs.
• Josh Naylor is hitting .253 with nine doubles, eight home runs and 23 walks, while slugging .372 with an on-base percentage of .314.
• His batting average ranks 76th among qualified players, his on-base percentage 108th, and his slugging percentage 119th.
• Naylor heads into this matchup looking to extend his three-game hit streak. During his last five outings he is batting .200 with two doubles, a home run and an RBI.
• Cole Young is batting .254 with a .366 slugging percentage and 34 RBI this year.
• Dominic Canzone has 11 home runs, 31 RBI and a batting average of .282 this season.

Red Sox Player Leaders

• Willson Contreras has totaled 73 hits with a .382 on-base percentage, leading the Red Sox in both statistics. He's batting .289 and slugging .538.
• He is 21st in batting average, 14th in on-base percentage and 12th in slugging percentage among all qualifying batters in MLB.
• Wilyer Abreu is slugging .423 to lead his team. He has a batting average of .274 with an on-base percentage of .332.
• His batting average ranks 45th among all qualified players, his on-base percentage is 84th, and he is 81st in slugging.
• Ceddanne Rafaela is batting .286 with 17 doubles, two triples, seven home runs and 14 walks.
• Jarren Duran is hitting .210 with nine doubles, two triples, 12 home runs and 20 walks.

Mariners vs Red Sox Head to Head

• 6/19/2026: 6-2 BOS (Favorite: Mariners, Spread: -1.5, Total: 6.5, Favorite Moneyline: -112, Underdog Moneyline: -104)
• 6/18/2025: 3-1 BOS (Favorite: Red Sox, Spread: -1.5, Total: 6.5, Favorite Moneyline: -118, Underdog Moneyline: -100)
• 6/17/2025: 8-0 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -162, Underdog Moneyline: +136)
• 6/16/2025: 2-0 BOS (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -178, Underdog Moneyline: +150)
• 4/24/2025: 4-3 SEA (Favorite: Red Sox, Spread: -1.5, Total: 8, Favorite Moneyline: -180, Underdog Moneyline: +152)
• 4/23/2025: 8-5 SEA (Favorite: Red Sox, Spread: -1.5, Total: 9.5, Favorite Moneyline: -136, Underdog Moneyline: +116)
• 4/22/2025: 8-3 BOS (Favorite: Red Sox, Spread: -1.5, Total: 9.5, Favorite Moneyline: -122, Underdog Moneyline: +104)
• 7/31/2024: 3-2 BOS (Favorite: Mariners, Spread: -1.5, Total: 9.5, Favorite Moneyline: -112, Underdog Moneyline: -104)
• 7/30/2024: 10-6 SEA (Favorite: Mariners, Spread: -1.5, Total: 10.5, Favorite Moneyline: -118, Underdog Moneyline: -100)
• 7/29/2024: 14-7 BOS (Favorite: Red Sox, Spread: -1.5, Total: 8.5, Favorite Moneyline: -120, Underdog Moneyline: +102)

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