Mariners vs Rockies Prediction, Odds, Moneyline, Spread & Over/Under for Sept. 20

Odds updated as of 10:15 p.m.

The Seattle Mariners versus the Colorado Rockies is on the MLB schedule for Sunday.

All the info you need to make smart wagers on this matchup at FanDuel Sportsbook can be found below. Check out all of the latest MLB betting lines here.

Mariners vs Rockies Game Info

• Seattle Mariners (72-82) vs. Colorado Rockies (56-98)
• Date: Sunday, September 20, 2026
• Time: 3:10 p.m. ET
• Venue: Coors Field -- Denver, Colorado
• Coverage: Rockies.TV and Mariners.TV

Mariners vs Rockies Odds & Moneyline

• All MLB odds, betting lines and prop bets are available on FanDuel Sportsbook.
• Moneyline: SEA: (-154) | COL: (+130)
• Spread: SEA: -1.5 (+104) | COL: +1.5 (-125)
• Total: 10.5 -- Over: (-122) | Under: (+100)

Mariners vs Rockies Probable Starting Pitchers

Probable Pitchers: Kade Anderson (Mariners) - 1-2, 5.33 ERA vs Kyle Freeland (Rockies) - 4-10, 6.38 ERA

The probable starters are Kade Anderson (1-2) for the Mariners and Kyle Freeland (4-10) for the Rockies. Anderson's team is 1-3-0 against the spread in his starts this season. When Anderson starts a game and his team is the favorite on the moneyline, they have a record of 2-2. When Freeland starts, the Rockies have gone 13-12-0 against the spread. The Rockies are 9-15 in Freeland's 24 starts this season that they were the moneyline underdog.

Mariners vs Rockies Prediction & Pick

All MLB win probability predictions and picks are according to numberFire.
Prediction: Mariners win (54.4%)

Mariners vs Rockies Moneyline

• Seattle is the favorite, -154 on the moneyline, while Colorado is a +130 underdog despite being at home.

Mariners vs Rockies Spread

• The Mariners are favored by 1.5 runs on the road versus the Rockies. The Mariners are +104 to cover the spread, while the Rockies are -125.

Mariners vs Rockies Over/Under

• The Mariners-Rockies contest on Sept. 20 has been given an over/under of 10.5 runs. The over is set at -122 and the under at +100.

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Mariners vs Rockies Betting Trends

• The Mariners have been victorious in 58, or 49.6%, of the 117 contests they have been chosen as favorites in this season.
• Seattle has a record of 20-15 in contests when sportsbooks favor them by -154 or more on the moneyline.
• The Mariners and their opponents have gone over the total this season in 81 of their 152 opportunities.
• The Mariners have posted a record of 56-96-0 against the spread this season.
• The Rockies have won 53 of the 147 games they were the moneyline underdog this season (36.1%).
• Colorado has a 30-74 record (winning only 28.8% of its games) when it has played as a moneyline underdog of +130 or longer.
• In the 151 games oddsmakers have set an over/under for the Rockies, they have combined with opponents to go over the total 75 times (75-73-3).
• The Rockies are 79-72-0 against the spread this season.

Mariners Player Leaders

• Randy Arozarena leads Seattle with an OBP of .378 this season while batting .281 with 63 walks and 104 runs scored. He has a slugging percentage of .480.
• Among the qualifying hitters in the majors, his batting average ranks 22nd, his on-base percentage ranks ninth, and he is 29th in slugging.
• Arozarena will look for his eighth straight game with a hit in this matchup. In his last 10 outings he is hitting .385 with three doubles, three home runs, four walks and nine RBIs.
• Josh Naylor has an OPS of .691, fueled by an OBP of .327 and a team-best slugging percentage of .364 this season. He's batting .272.
• He ranks 38th in batting average, 73rd in on-base percentage and 119th in slugging among qualifying batters.
• Naylor has picked up a hit in three games in a row. During his last five outings he is hitting .333 with a double, a walk and four RBIs.
• Cole Young has collected 137 base hits, an OBP of .309 and a slugging percentage of .387 this season.
• Julio Rodriguez has been key for Seattle with 137 hits, an OBP of .302 plus a slugging percentage of .394.

Rockies Player Leaders

• Jake McCarthy is batting .298 with 30 doubles, 12 triples, 15 home runs and 29 walks. He's slugging .490 with an on-base percentage of .342.
• Including all the qualifying hitters in the majors, his batting average places him eighth, his on-base percentage ranks 51st, and he is 20th in slugging.
• TJ Rumfield's .392 on-base percentage and .453 slugging percentage both lead his team. He has a batting average of .300.
• He is seventh in batting average, third in on-base percentage and 42nd in slugging percentage in MLB.
• Hunter Goodman has racked up 119 hits, a team-best for the Rockies.
• Kyle Karros has 21 doubles, three triples, 12 home runs and 50 walks while batting .259.

Mariners vs Rockies Head to Head

• 9/18/2026: 5-4 SEA (Favorite: Mariners, Spread: -1.5, Total: 10.5, Favorite Moneyline: -186, Underdog Moneyline: +156)
• 9/25/2025: 6-2 SEA (Favorite: Mariners, Spread: -1.5, Total: 7.5, Favorite Moneyline: -320, Underdog Moneyline: +260)
• 9/24/2025: 9-2 SEA (Favorite: Mariners, Spread: -1.5, Total: 7.5, Favorite Moneyline: -300, Underdog Moneyline: +245)
• 9/23/2025: 4-3 SEA (Favorite: Mariners, Spread: -1.5, Total: 8, Favorite Moneyline: -300, Underdog Moneyline: +245)
• 4/21/2024: 10-2 SEA (Favorite: Mariners, Spread: -1.5, Total: 11, Favorite Moneyline: -118, Underdog Moneyline: -100)
• 4/21/2024: 2-1 COL (Favorite: Mariners, Spread: -1.5, Total: 10.5, Favorite Moneyline: -190, Underdog Moneyline: +160)
• 4/20/2024: 7-0 SEA (Favorite: Mariners, Spread: -1.5, Total: 9.5, Favorite Moneyline: -184, Underdog Moneyline: +154)
• 4/16/2023: 1-0 SEA (Favorite: Mariners, Spread: -1.5, Total: 8, Favorite Moneyline: -300, Underdog Moneyline: +245)
• 4/15/2023: 9-2 SEA (Favorite: Mariners, Spread: -1.5, Total: 8, Favorite Moneyline: -250, Underdog Moneyline: +205)
• 4/14/2023: 5-3 SEA (Favorite: Mariners, Spread: -1.5, Total: 8.5, Favorite Moneyline: -178, Underdog Moneyline: +150)

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