Mariners vs Cubs Prediction, Odds, Moneyline, Spread & Over/Under for Aug. 21

Odds updated as of 5:12 a.m.

The MLB slate on Friday includes the Seattle Mariners taking on the Chicago Cubs.

We've got you covered, in terms of the most important info regarding this game before you take a look at the MLB odds and spreads on FanDuel Sportsbook.

Mariners vs Cubs Game Info

• Seattle Mariners (60-68) vs. Chicago Cubs (74-54)
• Date: Friday, August 21, 2026
• Time: 10:10 p.m. ET
• Venue: T-Mobile Park -- Seattle, Washington
• Coverage: Mariners.TV and MARQ

Mariners vs Cubs Odds & Moneyline

• All MLB odds, betting lines and prop bets are available on FanDuel Sportsbook.
• Moneyline: SEA: (-108) | CHC: (-108)
• Spread: SEA: +1.5 (-184) | CHC: -1.5 (+152)
• Total: 7.5 -- Over: (-122) | Under: (+100)

Mariners vs Cubs Probable Starting Pitchers

Probable Pitchers: Emerson Hancock (Mariners) - 7-7, 3.30 ERA vs Matthew Boyd (Cubs) - 8-2, 4.02 ERA

This contest's pitching matchup is set, as the Mariners will send Emerson Hancock (7-7) to the mound, while Matthew Boyd (8-2) will take the ball for the Cubs. When Hancock starts, his team is 8-15-0 against the spread this season. Hancock's team has been victorious in 47.1% of the games he's started as the moneyline favorite with a record of 8-9. The Cubs have a 9-5-0 ATS record in Boyd's 14 starts with a set spread. The Cubs have been the moneyline underdog in three of Boyd's starts this season, and they went 1-2 in those games.

Mariners vs Cubs Prediction & Pick

All MLB win probability predictions and picks are according to numberFire.
Prediction: Cubs win (51.9%)

Mariners vs Cubs Moneyline

• The Mariners vs Cubs moneyline has Seattle as a -108 favorite, while Chicago is a -108 underdog on the road.

Mariners vs Cubs Spread

Mariners vs Cubs Over/Under

• Mariners versus Cubs on Aug. 21 has an over/under of 7.5 runs, with the odds on the over -122 and the under set at +100.

Bet on Seattle Mariners vs. Chicago Cubs on FanDuel today!

Mariners vs Cubs Betting Trends

• The Mariners have won in 49, or 49.5%, of the 99 contests they have been named as odds-on favorites in this year.
• This year Seattle has won 50 of 100 games when listed as at least -108 on the moneyline.
• Contests with the Mariners have gone over the total set by oddsmakers in 63 of 127 chances this season.
• The Mariners are 45-82-0 against the spread in their 127 games that had a posted line this season.
• The Cubs have gone 21-16 in games they were the underdog on the moneyline (winning 56.8% of those games).
• Chicago is 21-16 (winning 56.8% of its games) when playing as a moneyline underdog of -108 or longer.
• In the 123 games bookmakers have set an over/under for the Cubs, they have combined with opponents to go over the total 66 times (66-57-0).
• The Cubs have collected a 61-62-0 record ATS this season (covering 49.6% of the time).

Mariners Player Leaders

• Randy Arozarena has 121 hits, which is tops among Seattle hitters this season, while batting .272 with 44 extra-base hits. He has an on-base percentage of .366 and a slugging percentage of .449.
• Among the qualifying hitters in MLB, his batting average ranks 38th, his on-base percentage ranks 21st, and he is 47th in slugging.
• Josh Naylor has hit 10 homers this season while driving in 46 runs. He's batting .268 this season and slugging .371 with an on-base percentage of .330.
• He ranks 46th in batting average, 76th in on-base percentage and 119th in slugging in the major leagues.
• Julio Rodriguez is batting .253 with a .416 slugging percentage and 53 RBI this year.
• Cole Young is batting .254 with a .314 OBP and 56 RBI for Seattle this season.

Cubs Player Leaders

• Pete Crow-Armstrong has racked up a team-best OBP (.378) and slugging percentage (.550), while leading the Cubs in hits (136, while batting .279).
• Including all qualified hitters in the majors, he is 28th in batting average, 11th in on-base percentage and third in slugging percentage.
• Alex Bregman is batting .255 with 24 doubles, a triple, 16 home runs and 63 walks. He's slugging .404 with an on-base percentage of .345.
• Including all qualified hitters, his batting average puts him 74th, his on-base percentage is 53rd, and he is 92nd in slugging.
• Nico Hoerner is batting .264 with 26 doubles, a triple, seven home runs and 40 walks.
• Seiya Suzuki has 24 doubles, 22 home runs and 58 walks while hitting .268.

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