The Houston Astros take on the Seattle Mariners. Our MLB odds series has our Astros Mariners prediction and pick. Find out how to watch Astros Mariners.

The Houston Astros and Seattle Mariners have split the first two games of their showdown series in Seattle. This leaves Houston half a game ahead of the Mariners for the third and final wild card spot in the American League. It's a massive game whose outcome will probably — but not certainly — determine the winner of the final wild card spot in the A.L.

If Houston wins, it will take a 1.5-game lead over the Mariners heading into Thursday. Houston will not play on Thursday while Seattle will host the Texas Rangers. If Seattle loses to Texas on Thursday, Houston would then lead by two games with three to play, which is a commanding position.

If Seattle wins this game, it takes a half-game lead over Houston heading into Thursday. If the Mariners win on Thursday, they would lead Houston by a game with three left. If the Astros trail the Mariners heading into Friday — which could easily happen if they lose this game on Wednesday — they will be in huge trouble.

The Astros, as defending champions, are playing to ensure they get to defend their championship in the postseason, a big point of pride for all the stars on this team. The Mariners, having been eliminated from the playoffs by the Astros last year, would love nothing more than to beat Houston in a high-stakes situation. Game on in Seattle.

Here are the Astros-Mariners MLB odds, courtesy of FanDuel. 

MLB Odds: Astros-Mariners Odds

Houston Astros: -1.5 (+140)

Seattle Mariners: +1.5 (-170)

Over: 7.5 (-122)

Under: 7.5 (+100)

How To Watch Astros vs. Mariners

TV: AT&T SportsNet Houston (Astros) / Root Sports (Mariners) / MLB Extra Innings, MLB Network (National)

Stream: MLB.tv

Time: 9:40 p.m. ET/6:40 p.m. PT

*Watch Astros-Mariners LIVE on fuboTV (click for a free trial)*

Why The Astros Could Cover The Spread

The Astros stumbled on Tuesday, but let's remember that the main objective for Houston was to win two of three in Seattle. The Astros are in position to do that on Wednesday night. Tuesday night was an important game but not a must-win game. This is the must-win game. Let's go back to something we said on Monday night before Justin Verlander beat the Mariners in the first game of the series: The Astros might stumble at times versus the Mariners, but they beat Seattle when it really, really matters. This is the game which really, really matters.

Add to this the fact that Houston is sending Framber Valdez to the mound. Verlander is the ace, but Framber is an ace-quality pitcher as well. He hasn't had a great year, but he has pitched several great games. This is a moment in which he historically raises his level of performance. Framber is worthy of trust.

Why The Mariners Could Cover The Spread

The Mariners have Bryce Miller on the mound. His 4.17 ERA suggests he is an average pitcher, but if you look at his starts from 2023, you will see that three of every four starts are good to very good. Then he produces a clunker in that fourth start, which blows up his ERA. Miller will give up one or two runs in a few starts and then give up seven. Most of the time, he's very good. He will relish this situation here and will have a roaring home crowd supporting him all the way. He is extremely talented and should have no problem getting a lot of mustard and bite on his above-average fastball. He can blow away Houston hitters if he locates the fastball.

Framber Valdez is a high-level pitcher for Houston, but he has had his share of struggles. The fact that he got tagged by the Kansas City Royals in his most recent start — when the Astros needed something really good from him — is a sign of real concern for the Astros.

Final Astros-Mariners Prediction & Pick

Framber Valdez is a proven, experienced, big-game pitcher. That means a lot in a situation like this. Take the Astros.

Final Astros-Mariners Prediction & Pick: Astros -1.5