Mariners vs Athletics Prediction, Odds, Moneyline, Spread & Over/Under for April 20

Odds updated as of 5:12 a.m.

In MLB action on Monday, the Seattle Mariners face the Athletics.

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

Mariners vs Athletics Game Info

• Seattle Mariners (10-13) vs. Athletics (11-11)
• Date: Monday, April 20, 2026
• Time: 9:40 p.m. ET
• Venue: T-Mobile Park -- Seattle, Washington
• Coverage: Mariners.TV and NBCS-CA

Mariners vs Athletics Odds & Moneyline

• All MLB odds, betting lines and prop bets are available on FanDuel Sportsbook.
• Moneyline: SEA: (-158) | OAK: (+134)
• Spread: SEA: -1.5 (+136) | OAK: +1.5 (-164)
• Total: 8 -- Over: (-115) | Under: (-105)

Mariners vs Athletics Probable Starting Pitchers

Probable Pitchers: Emerson Hancock (Mariners) - 2-1, 2.28 ERA vs J.T. Ginn (Athletics) - 0-0, 3.31 ERA

The Mariners will give the nod to Emerson Hancock (2-1, 2.28 ERA), who is eyeing win No. 3 on the season, and the Athletics will turn to J.T. Ginn. Hancock and his team are 2-2-0 ATS this season when he starts. When Hancock starts a game and his team is the favorite on the moneyline, they have a record of 2-1. Ginn has started two games with set spreads, and the Athletics covered in both chances. The Athletics were the underdog on the moneyline for one Ginn start this season -- they won.

Mariners vs Athletics Prediction & Pick

All MLB win probability predictions and picks are according to numberFire.
Prediction: Mariners win (55.1%)

Mariners vs Athletics Moneyline

• The Mariners vs Athletics moneyline has the Mariners as a -158 favorite, while the Athletics are a +134 underdog on the road.

Mariners vs Athletics Spread

• The Mariners are 1.5-run favorites on the runline against the Athletics. The Mariners are +136 to cover, while the Athletics are -164 to cover.

Mariners vs Athletics Over/Under

• The over/under for the Mariners versus Athletics contest on April 20 has been set at 8, with -115 odds on the over and -105 odds on the under.

Bet on Seattle Mariners vs. Athletics on FanDuel today!

Mariners vs Athletics Betting Trends

• The Mariners have won in nine, or 47.4%, of the 19 contests they have been named as odds-on favorites in this year.
• This season, the Mariners have come away with a win four times in seven chances when named as a favorite of at least -158 or shorter on the moneyline.
• The Mariners and their opponents have hit the over in 10 of their 23 games with a total this season.
• The Mariners have posted a record of 9-14-0 against the spread this season.
• The Athletics have gone 8-8 in games they were the underdog on the moneyline (winning 50% of those games).
• The Athletics have a record of 4-4 in games they have played as a moneyline underdog with odds of +134 or longer (50%).
• The Athletics have combined with their opponents to go over the total 11 times this season for an 11-11-0 record against the over/under.
• The Athletics have a 12-10-0 record ATS this season (covering 54.5% of the time).

Mariners Player Leaders

• Randy Arozarena leads Seattle with a slugging percentage of .427, fueled by seven extra-base hits. He has a .293 batting average and an on-base percentage of .402.
• Among qualified hitters in the majors, his batting average ranks 34th, his on-base percentage ranks 17th, and he is 73rd in slugging.
• Arozarena hopes to build on a two-game hitting streak in this matchup. During his last five outings he is hitting .316 with two doubles, a home run, two walks and two RBIs.
• Luke Raley leads Seattle in total hits (21) this season while batting .313 with 10 extra-base hits. He's slugging .627 with an on-base percentage of .370.
• Among qualified hitters, his batting average ranks him 14th, his on-base percentage 42nd, and his slugging percentage fifth.
• Cole Young has 19 hits this season and has a slash line of .244/.344/.372.
• Young brings a four-game hitting streak into this game. In his last five games he is batting .294 with four walks and two RBIs.
• Brendan Donovan has 17 hits this season and a team-best OBP of .437.

Athletics Player Leaders

• Shea Langeliers has put up a slugging percentage of .571 and has 26 hits, both team-high numbers for the Athletics. He's batting .310 and with an on-base percentage of .376.
• Including all the qualifying hitters in the big leagues, his batting average is 19th, his on-base percentage is 35th, and he is 12th in slugging.
• Tyler Soderstrom is hitting .202 with six doubles, a triple, two home runs and 11 walks. He's slugging .369 with an on-base percentage of .295.
• Including all qualifying players, he is 151st in batting average, 138th in on-base percentage and 110th in slugging percentage.
• Jacob Wilson is batting .253 with three doubles, two home runs and a walk.
• Nick Kurtz paces his team with a .421 OBP.

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