Mariners vs. Cubs Prediction, Odds, Probable Pitchers and Prop Bets for Friday, June 20

Betting odds, pick and prediction for the Seattle Mariners-Chicago Cubs matchup on June 20.

The Cubs are favored at home on Friday. / Geoff Burke-Imagn Images

The only afternoon matchup in Major League Baseball on Friday features the NL Central-leading Chicago Cubs opening a weekend series against the Seattle Mariners.

Seattle has fallen out of first place in the AL West, dropping to five games back of the Houston Astros after a strong start to the season.

On Friday, Seattle is a road underdog with George Kirby (5.96 ERA) set to make his sixth start of the 2025 season after missing the beginning of the campaign on the IL.

Chicago will counter with veteran lefty Matthew Boyd, who has a 2.79 ERA in 14 appearances in 2025.

Let’s take a look at the odds, players to bet on in the prop market and my prediction for Friday afternoon’s contest. 

Mariners vs. Cubs Odds, Run Line and Total

Odds via DraftKings Sportsbook.

Run Line

• Mariners +1.5 (-196)
• Cubs -1.5 (+160)

Moneyline

• Mariners: +118
• Cubs: -144

Total

• 9.5 (Over -115/Under -105)

Mariners vs. Cubs Probable Pitchers

• Seattle: George Kirby (1-3, 5.96 ERA)
• Chicago: Matthew Boyd (6-3, 2.79 ERA)

Mariners vs. Cubs How to Watch

• Date: Friday, June 20
• Time: 2:20 p.m. EST
• Venue: Wrigley Field
• How to Watch (TV): MLB Network, MARQ, ROOT Sports NW
• Mariners record: 37-36
• Cubs record: 45-29

Mariners vs. Cubs Best MLB Prop Bets

Mariners Best MLB Prop Bet

• George Kirby OVER 4.5 Strikeouts (-165)

Even though Kirby hasn’t gotten off to the best start in the 2025 season, he still ranks in the 79th percentile in strikeout percentage and 65th percentile in chase rate. 

Kirby’s numbers are buoyed by a 14-strikeout game, but he’s cleared 4.5 punchouts in back-to-back games, striking out 30 batters in 25.2 innings of work. 

The Cubs are averaging just under eight strikeouts per game, but if Kirby works past the fifth inning, he’s a pretty solid bet to record five or more punchouts. Last season, the Mariners righty had the best strikeout/walk ratio in MLB at 7.78. 

Mariners vs. Cubs Prediction and Pick

The Cubs are 24-13 at home this season, and I think they’re worth a look on the moneyline in this afternoon matchup against a Mariners team that is in danger of falling under .500 in the 2025 season. 

Chicago is just 7-7 in Boyd’s outings this season, but the lefty has been great in June, allowing just five runs (four earned) across three starts (1.86 ERA). He has lowered his expected ERA to 3.58 this season, which is far better than Kirby (4.48 xERA). 

The Mariners righty got off to a slow start in his first two outings of the season, but I’m not totally sold on him turning things around against one of the best offenses in baseball. Kirby allowed the most hits in the American League in 2024 (181), and the Cubs rank in the top six in MLB in runs scored, batting average and OPS.

I think Chicago improves upon its record at home in the 2025 season. 

Pick: Cubs Moneyline (-144 at DraftKings)

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Odds refresh periodically and are subject to change.

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