Mariners vs Giants Prediction, Odds, Moneyline, Spread & Over/Under for July 18

Odds updated as of 5:13 a.m.

MLB action on Saturday includes the Seattle Mariners facing the San Francisco Giants.

We've got you covered, in terms of the vital info about this matchup before you take a look at the MLB odds and spreads on FanDuel Sportsbook.

Mariners vs Giants Game Info

• Seattle Mariners (48-50) vs. San Francisco Giants (42-55)
• Date: Saturday, July 18, 2026
• Time: 8:08 p.m. ET
• Venue: T-Mobile Park -- Seattle, Washington
• Coverage: FOX

Mariners vs Giants Odds & Moneyline

• All MLB odds, betting lines and prop bets are available on FanDuel Sportsbook.
• Moneyline: SEA: (-136) | SF: (+116)
• Spread: SEA: -1.5 (+164) | SF: +1.5 (-200)
• Total: 7 -- Over: (-102) | Under: (-120)

Mariners vs Giants Probable Starting Pitchers

Probable Pitchers: Bryan Woo (Mariners) - 7-6, 4.23 ERA vs Logan Webb (Giants) - 5-7, 3.86 ERA

This contest's pitching matchup is set, as the Mariners will send Bryan Woo (7-6) to the mound, while Logan Webb (5-7) will answer the bell for the Giants. Woo and his team are 9-9-0 ATS this season when he starts. Woo's team has a record of 9-7 this season when he starts and they are the favorite on the moneyline. The Giants are 6-10-0 ATS in Webb's 16 starts that had a set spread. The Giants have a 1-4 record in Webb's five starts this season when they were the underdog on the moneyline.

Mariners vs Giants Prediction & Pick

All MLB win probability predictions and picks are according to numberFire.
Prediction: Mariners win (55.2%)

Mariners vs Giants Moneyline

• Looking at the moneyline for Giants-Mariners, San Francisco is the underdog at +116, and Seattle is -136 playing at home.

Mariners vs Giants Spread

• The Mariners are hosting the Giants and are favored by 1.5 runs (+164 to cover) on the runline. San Francisco is -200 to cover.

Mariners vs Giants Over/Under

• An over/under of 7 has been set for Mariners-Giants on July 18, with the over being -102 and the under -120.

Bet on Seattle Mariners vs. San Francisco Giants on FanDuel today!

Mariners vs Giants Betting Trends

• The Mariners have won in 43, or 52.4%, of the 82 contests they have been named as odds-on favorites in this year.
• This season Seattle has been victorious 27 times in 45 chances when named as a favorite of at least -136 on the moneyline.
• The Mariners and their opponents have gone over the total this season in 46 of their 97 opportunities.
• The Mariners have an against the spread mark of 35-62-0 in 97 games with a line this season.
• The Giants have put together a 22-36 record in games they were the underdog on the moneyline (winning 37.9% of those games).
• San Francisco has gone 10-11 in games it has played as a moneyline underdog with odds of +116 or longer (47.6%).
• The Giants have played in 94 games with a set over/under, and have combined with opponents to go over the total 44 times (44-43-7).
• The Giants are 42-52-0 ATS this season.

Mariners Player Leaders

• Randy Arozarena leads Seattle in OBP (.376), slugging percentage (.453) and total hits (93) this season. He has a .283 batting average.
• Among all qualifying hitters in MLB, his batting average ranks 27th, his on-base percentage ranks 18th, and he is 58th in slugging.
• Josh Naylor is batting .253 with 12 doubles, eight home runs and 30 walks. He's slugging .354 with an on-base percentage of .317.
• Among qualified hitters, he ranks 79th in batting average, 98th in on-base percentage and 129th in slugging percentage.
• Naylor brings a nine-game streak with at least one hit into this matchup. During his last 10 outings he is hitting .243 with a double, three walks and two RBIs.
• Cole Young has 88 hits this season and has a slash line of .251/.311/.390.
• Dominic Canzone is batting .261 with a .333 OBP and 40 RBI for Seattle this season.

Giants Player Leaders

• Luis Arraez has put up an on-base percentage of .367 and a slugging percentage of .456. Both lead the Giants. He's batting .328.
• Including all qualified hitters, he ranks second in batting average, while his on-base percentage ranks 27th and he is 55th in slugging.
• Casey Schmitt's 100 hits pace his team. He has a batting average of .282 while slugging .496 with an on-base percentage of .309.
• Including all qualifying players, he ranks 30th in batting average, 112th in on-base percentage and 24th in slugging percentage.
• Jung Hoo Lee has 21 doubles, three triples, five home runs and 14 walks while hitting .307.
• Rafael Devers has 25 doubles, a triple, 19 home runs and 38 walks while hitting .246.

Mariners vs Giants Head to Head

• 7/17/2026: 7-0 SF (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -184, Underdog Moneyline: +154)
• 4/6/2025: 5-4 SF (Favorite: Giants, Spread: -1.5, Total: 7.5, Favorite Moneyline: -118, Underdog Moneyline: -100)
• 4/5/2025: 4-1 SF (Favorite: Giants, Spread: -1.5, Total: 7.5, Favorite Moneyline: -120, Underdog Moneyline: +102)
• 4/4/2025: 10-9 SF (Favorite: Giants, Spread: -1.5, Total: 7.5, Favorite Moneyline: -148, Underdog Moneyline: +126)
• 8/25/2024: 4-3 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -142, Underdog Moneyline: +120)
• 8/24/2024: 4-3 SF (Favorite: Mariners, Spread: -1.5, Total: 6, Favorite Moneyline: -112, Underdog Moneyline: -104)
• 8/23/2024: 6-5 SEA (Favorite: Mariners, Spread: -1.5, Total: 7, Favorite Moneyline: -148, Underdog Moneyline: +126)
• 7/5/2023: 2-0 SF (Favorite: Giants, Spread: -1.5, Total: 8.5, Favorite Moneyline: -174, Underdog Moneyline: +146)
• 7/4/2023: 6-0 SEA (Favorite: Giants, Spread: -1.5, Total: 8.5, Favorite Moneyline: -120, Underdog Moneyline: +102)

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