Boston Red Sox vs Seattle Mariners Prediction, Odds and Picks for Today, 06/18/25

The only afternoon game on Wednesday is in the Pacific Northwest, where the Boston Red Sox face the Seattle Mariners. These teams have split the series so far, with Boston winning Monday’s game 2-0 while the Mariners won Tuesday’s affair 8-0. Tuesday was all about Cal Raleigh, who drove in nearly every run of the game. That ended a 6-game winning streak for the Red Sox, despite trading their best hitter in the middle of all that. On Wednesday, I think the play is the Under, even at an absurdly low 7 runs.

All we need to hit that Under is both starters to perform at their normal level. Both Garrett Crochet and Luis Castillo are in great form, and we should have a quiet first 5 or 6 innings before handing things off to the bullpens. We might even get lucky and see Raleigh sit since it is a day game after a night game, but even if he plays, there’s a chance Seattle will simply try to walk him. On the Boston side, not only did they trade Rafael Devers, but even during their winning streak, they weren’t scoring. They were winning with pitching. This has all the makings of a 3-2 type of game. The books are daring us to take the Over, and I think that is a trap. Let’s roll with the Under.

Red Sox vs Mariners prediction: Under 7 (-125) available at time of publishing. Playable at that number.

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