Mariners vs. Cubs Dunkel MLB Picks, Predictions and Prop Bets - Aug. 21

The Seattle Mariners host the Chicago Cubs to start a three-game series at T-Mobile Park, with first pitch at 10:10 p.m. ET on Friday. Emerson Hancock (7-7, 3.30 ERA) will start for the Mariners, who are 60-68 this season and third in the AL West. Matthew Boyd (8-2, 4.02 ERA) is starting for the Cubs, who are 74-54 and second in the NL Central.

Sportsbooks expect a close matchup between the Mariners (-109 to win) and the Cubs (-105). The over/under for this contest is set at 8.

Mariners vs. Cubs Odds, Game Time

• Game day: Friday, August 21, 2026
• Game time: 10:10 p.m. ET
• Location: Seattle, Washington
• Stadium: T-Mobile Park
• Favorite: Mariners (-109)
• Underdog: Cubs (-105)
• Over/under: 8

How to Watch Mariners vs. Cubs

• TV Channel: SEAM and MARQ
• Live Stream: Fubo (Watch for free)

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Mariners vs. Cubs: Betting the Moneyline

• The Mariners have been favored on the moneyline 100 total times this season. They've gone 50-50 in those games.
• Chicago has been pegged as an underdog in 38 games this year and has walked away with the win 22 times (57.9%) in those games.
• Seattle is 51-50 this season when entering a game favored by -109 or more on the moneyline.
• This season, the Cubs have been victorious 19 times in 34 chances when named as an underdog of at least -105 or worse on the moneyline.
• The implied moneyline probablility for this matchup gives the Mariners a 52.2% chance to win.
• Bookmakers have implied with the moneyline set for this matchup that the Cubs have a 51.2% chance of pulling out a win.

Mariners vs. Cubs: Betting the Spread & Total

• The Mariners have combined with opponents to hit the over on the total 63 times this season for a 63-57-8 record against the over/under.
• Chicago and its opponents have gone over the total this season in 68 of its 128 opportunities.
• The Mariners have a 47-81-0 record against the spread this season.
• The Cubs have posted a record of 61-67-0 against the spread this season.