Astros vs. Mariners Prediction, Odds & Best Bets: Can Walter Stifle Seattle?

Brandon Walter has been mostly impressive during his first few starts for the Astros, and he'll be a challenge for Seattle.
Astros vs. Mariners Prediction, Odds & Best Bets: Friday, July 18
Pictured: Houston Astros starting pitcher Brandon Walter walks to the dugout, and he's key to our Astros vs. Mariners prediction. Photo by Kim Klement Neitzel via Imagn Images.

A monumental divisional series is featured to open up the second half of the MLB season as we make our Astros vs. Mariners prediction.

The Astros own the second-best record in the American League (56-40), and they'll look to keep the Mariners behind them in the AL West. Seattle is five games back of divisional-leading Houston, and this is an ideal opportunity to close the gap.

This game is a tossup at most of the best MLB betting sites. However, there's one book offering an outlier price on the Astros that you should pounce on now for one of your Astros vs. Mariners best bets, well ahead of first pitch at 10:10 p.m. ET (Root Sports) tomorrow night from T-Mobile Park in Seattle.

  • Astros vs. Mariners prediction: Astros to win (+108 via FanDuel) ⭐⭐⭐⭐⭐

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✅ Astros vs. Mariners prediction: Astros to win (+108 via FanDuel)

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There are benefits to making an early pick, as sometimes you're able to throw yourself at a rogue price from one of our best sports betting sites. That's the case here while making your Astros vs. Mariners prediction, with Houston backers getting plus-money odds from FanDuel.

It's the only such offering for your Astros vs. Mariners best bet for the World Series odds contenders, with the rest of the best sports betting apps listing the game at or near a pick 'em.

FanDuel is probably listing the Mariners as -126 betting favorites in part due to the likely presence of All-Star Bryan Woo on the mound for Seattle, giving the home side a notable pitching edge over Houston, with the Astros sending out Brandon Walter. The latter is making just his eighth big-league start.

But Walter has been shining, albeit in a small sample size.

He's endured two blowups with five-plus earned runs, though the always unfriendly pitching confines of Coors Field played a significant role in one. But he's allowed two or fewer runs in his other five outings, including a five-inning shutout during his first major-league start against the Tampa Bay Rays and their ninth-ranked offense.

His control has been sparkling, with a mere two walks given up across 40 2/3 innings, leading to a walk rate that sits in the top 1% of MLB. Walter's average exit velocity allowed rests in the 97th percentile, according to Baseball Savant, showing he's not filling the zone with cookies either.

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❓MLB betting FAQs

How do betting odds work?

Betting odds represent the probability of a specific outcome and determine how much money you can win on a bet. There are three main formats: American odds, Decimal odds, and Fractional odds. In the U.S., American odds are most common. 

What is the run line in baseball?

The run line in baseball is a form of point spread betting unique to MLB. It typically sets a standard spread of 1.5 runs, meaning the favored team must win by at least two runs to cover the run line, while the underdog can lose by one run or win outright to cover.

What does moneyline mean in betting?

The moneyline in betting refers to a wager on which team or player will win the game outright, with no point spread involved. It’s the most straightforward type of sports bet—just pick the winner.

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