Astros vs. Mariners odds, line, prediction: 2026 MLB picks for Monday afternoon from proven model

The Seattle Mariners look to sweep their four-game wrap-around series with the Houston Astros when they meet in a key American League West Division matchup on Monday afternoon. Seattle is coming off a 6-1 win over Houston on Sunday. The Astros (6-10), who have lost seven in a row, are 1-8 on the road this season. The Mariners (7-9), who have won three in a row, are 6-4 on their home field in 2026.

First pitch from T-Mobile Park in Seattle is set for 4:10 p.m. ET. The Astros lead the all-time series 135-100, but the Mariners have won each of the last six meetings. Seattle is a -172 favorite on the money line (risk $172 to win $100) in the latest Astros vs. Mariners odds, while the over/under, is 7.5. Before making any Astros vs. Mariners picks, or MLB predictions, you NEED to see what the SportsLine Projection Model has to say.

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The model has simulated Astros vs. Mariners 10,000 times and the results are in. The model is going Over on the total, and is also says one side of the money line has ALL the value!

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