Colorado Rockies vs Seattle Mariners Prediction, Odds and Picks for Wednesday, 09/24/25

The Colorado Rockies are simply playing out the string, while the Seattle Mariners are looking to clinch a division title. Seattle punched its ticket to the postseason with a 4-3 comeback victory in Tuesday’s interleague series opener. Now the Mariners can celebrate on a second straight night with a victory, securing a division title. As it stands, Seattle is going to the playoffs for just the second time since 2001. Josh Naylor, an addition at the trade deadline from Arizona, picked up a big 2-out, bases-clearing double in the eighth inning to erase a 3-1 deficit.

The Mariners improved to 23-20 against the National League while moving to 49-27 at home. The Rockies have now lost a ridiculous 114 games and they are 40 games under .500 on the road at 18-58. Seattle should be able to cover the run line behind RHP Luis Castillo, who has mediocre numbers overall but a 2.71 ERA and 1.03 WHIP across 93.0 innings in 16 starts at home with opponents hitting just .202 against him. Look for Castillo to pitch the M’s to the division title in convincing fashion.

Rockies vs Mariners prediction: Mariners -1.5 (-135) available at time of publishing. Playable to -150.

If you’re looking for a new sportsbook for the football season, we recommend checking out Fanatics Sportsbook. New users can get up to $100 back in FanCash EVERY GAMEDAY UNTIL OCTOBER if their football bet loses! Join Fanatics Sportsbook, where you can bet on our Rockies vs Mariners predictions.