Mariners vs Diamondbacks Prediction, Odds, Moneyline, Spread & Over/Under for May 31

Odds updated as of 4:11 p.m.

The Seattle Mariners will take on the Arizona Diamondbacks in MLB action on Sunday.

Here's everything you need to know before checking out today's MLB odds and spreads on FanDuel Sportsbook.

Mariners vs Diamondbacks Game Info

• Seattle Mariners (30-29) vs. Arizona Diamondbacks (31-26)
• Date: Sunday, May 31, 2026
• Time: 4:10 p.m. ET
• Venue: T-Mobile Park -- Seattle, Washington
• Coverage: Mariners.TV and Dbacks.TV

Mariners vs Diamondbacks Odds & Moneyline

• All MLB odds, betting lines and prop bets are available on FanDuel Sportsbook.
• Moneyline: SEA: (-148) | ARI: (+126)
• Spread: SEA: -1.5 (+142) | ARI: +1.5 (-172)
• Total: 7 -- Over: (-102) | Under: (-120)

Mariners vs Diamondbacks Probable Starting Pitchers

Probable Pitchers: Bryce Miller (Mariners) - 1-0, 2.25 ERA vs Merrill Kelly (Diamondbacks) - 5-3, 5.25 ERA

The probable starters are Bryce Miller (1-0) for the Mariners and Merrill Kelly (5-3) for the Diamondbacks. Miller has a record of 0-2-0 ATS in two starts with a spread this season. Miller's team is 0-2 this season when he starts and they're favored on the moneyline. The Diamondbacks have a 5-3-0 record against the spread in Kelly's starts. The Diamondbacks have been the moneyline underdog in four of Kelly's starts this season, and they went 2-2 in those matchups.

Mariners vs Diamondbacks Moneyline

• Looking at the moneyline for Mariners-Diamondbacks, Seattle is the favorite at -148, and Arizona is +126 playing on the road.

Mariners vs Diamondbacks Spread

• The Diamondbacks are +1.5 on the run line against the Mariners. The Diamondbacks are -172 to cover, and the Mariners are +142.

Mariners vs Diamondbacks Over/Under

• The over/under for Mariners-Diamondbacks on May 31 is 7. The over is -102, and the under is -120.

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Mariners vs Diamondbacks Betting Trends

• The Mariners have been victorious in 28, or 51.9%, of the 54 contests they have been chosen as favorites in this season.
• This year Seattle has won 11 of 18 games when listed as at least -148 on the moneyline.
• The Mariners and their opponents have hit the over in 27 of their 59 games with a total set by oddsmakers this season.
• In 59 games with a line this season, the Mariners have a mark of 23-36-0 against the spread.
• The Diamondbacks have an 11-19 record in games they were listed as the moneyline underdog (winning 36.7% of those games).
• Arizona is 5-7 (winning 41.7% of its games) when playing as a moneyline underdog of +126 or longer.
• In the 56 games oddsmakers have set an over/under for the Diamondbacks, they have combined with opponents to go over the total 28 times (28-26-2).
• The Diamondbacks have a 33-23-0 record ATS this season (covering 58.9% of the time).

Mariners Player Leaders

• Julio Rodriguez leads Seattle with 64 hits and a team-best slugging percentage of .475. He's batting .269 with an on-base percentage of .326.
• Among qualified hitters in the majors, he ranks 51st in batting average, 92nd in on-base percentage, and 41st in slugging.
• Rodriguez will look for his seventh straight game with a hit in this contest. During his last 10 games he is batting .349 with four doubles, four home runs, a walk and nine RBIs.
• Randy Arozarena leads Seattle in OBP (.376) this season, fueled by 63 hits. He's batting .292 while slugging .458.
• His batting average ranks 19th among qualified players, his on-base percentage 23rd, and his slugging percentage 50th.
• Josh Naylor has 55 hits this season and has a slash line of .253/.318/.346.
• J.P. Crawford is batting .219 with a .343 OBP and 22 RBI for Seattle this season.
• Crawford takes a six-game hitting streak into this matchup. During his last 10 games he is batting .231 with three home runs, a walk and six RBIs.

Diamondbacks Player Leaders

• Corbin Carroll has racked up 57 hits with a .384 on-base percentage, leading the Diamondbacks in both categories. He's batting .288 and slugging .535.
• Including all the qualifying hitters in the majors, his batting average ranks 25th, his on-base percentage is 19th, and he is 16th in slugging.
• Ketel Marte's .459 slugging percentage paces his team. He has a batting average of .266 with an on-base percentage of .321.
• Including all qualified hitters, he ranks 58th in batting average, 98th in on-base percentage and 49th in slugging percentage.
• Ildemaro Vargas has racked up a team-best .469 slugging percentage.
• Geraldo Perdomo is batting .229 with nine doubles, three triples, three home runs and 33 walks.

Mariners vs Diamondbacks Head to Head

• 5/30/2026: 5-1 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -148, Underdog Moneyline: +126)
• 5/29/2026: 7-6 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -142, Underdog Moneyline: +120)
• 6/11/2025: 5-2 ARI (Favorite: Diamondbacks, Spread: -1.5, Total: 9, Favorite Moneyline: -112, Underdog Moneyline: -104)
• 6/10/2025: 10-3 ARI (Favorite: Diamondbacks, Spread: -1.5, Total: 9.5, Favorite Moneyline: -136, Underdog Moneyline: +116)
• 6/9/2025: 8-4 ARI (Favorite: Diamondbacks, Spread: -1.5, Total: 9, Favorite Moneyline: -174, Underdog Moneyline: +146)
• 4/28/2024: 3-2 ARI (Favorite: Mariners, Spread: -1.5, Total: 6.5, Favorite Moneyline: -136, Underdog Moneyline: +116)
• 4/27/2024: 3-1 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -156, Underdog Moneyline: +132)
• 4/26/2024: 6-1 SEA (Favorite: Diamondbacks, Spread: -1.5, Total: 7.5, Favorite Moneyline: -126, Underdog Moneyline: +108)
• 7/30/2023: 4-0 SEA (Favorite: Diamondbacks, Spread: -1.5, Total: 8, Favorite Moneyline: -110, Underdog Moneyline: -106)
• 7/29/2023: 4-3 ARI (Favorite: Mariners, Spread: -1.5, Total: 9, Favorite Moneyline: -110, Underdog Moneyline: -106)

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