Astros vs Mariners Game 3 Predictions

Frank AmmiranteSenior Sports Writer
Last Updated: Oct 15, 2022

The Seattle Mariners look to continue their magical run, set to take on their division rivals in the Houston Astros in the American League Division Series. Seattle went 7-12 in the season series against Houston this season.

They’ll look to avoid elimination in Game 3 as the series heads to Seattle. Slowing down the red-hot Yordan Álvarez is a major priority right now, as he’s been lethal in the first two games.

Let’s analyze the head-to-head matchup to determine predictions and best bets for Game 3 of the Mariners and Astros in the ALDS.

Mariners vs Astros Game 3 Odds

The Astros are -116 favorites with Lance McCullers Jr. on the mound against rookie George Kirby. The Mariners have advantages in pitching and home field here, making them a solid play at the -102 price.

The total is at seven runs for the second straight game. After we saw 15 runs in Game 1, it was a lower-scoring affair in Game 2, with the Astros winning, 4-2. The Under looks like the safer pick here.

Mariners vs Astros Game 3 Prediction

Mariners 3, Astros 2

I’m betting on the Mariners to avoid the sweep with Kirby on the mound. The rookie righty was highly impressive throughout his debut season, putting up a 3.39 ERA and 1.21 WHIP in 130 innings. What’s most intriguing is his 20.5% strikeout-to-walk ratio, which ranked 10th in MLB.

McCullers showed some issues with control (11.3 BB%) in limited action (47.2 innings), but the strikeouts (25.6 K%) were there. He finished his season strong, allowing two runs or fewer in his last six starts, spanning 36.2 innings.

This will be the first appearance of this year’s postseason for the Astros’ righty, while Kirby came in for a scoreless inning to shut the door on the Blue Jays in Game 2 of the American League Wild Card Series.

The Mariners will be playing their first home game of the playoffs here, as they try to avoid the sweep. In fact, it’s their first playoff game in Seattle in 21 years. The atmosphere at T-Mobile Park will be electric for this game.

Let’s face it: the Mariners deserve better than the 0-2 deficit that they’re currently facing. They let Game 1 slip away, but I don’t think they’ll be swept by the Astros. Look for a quality start for Kirby and a win for the home team.

Mariners vs Astros Game 3 Best Bet

Mariners (-102) at FanDuel Sportsbook

WAGER: 1 Unit

The fact that we’re getting the Mariners as home underdogs even though they have the pitching advantage makes this a strong play in my eyes. Houston is the better team but look for Seattle to make their fans proud in their first home playoff game in over two decades.

Mariners vs Astros Game 3 Props

Yordan Álvarez Over 1.5 Total Bases (-105) at FanDuel Sportsbook

WAGER: 1 Unit

Álvarez is absolutely mashing right now, going 4-for-8 with two home runs and one double. Kirby is a good young pitcher, but his low walk rate means more pitches in the zone for Álvarez. While you prefer to get plus money on this type of prop, I’ll take the -105 odds on one of the best hitters in baseball.

MLB Division Series Props

PREVIOUS: Mariners vs Astros Game 2 Prediction

Mariners 4, Astros 3

Castillo looked phenomenal in his previous outing, pitching 7.1 shutout innings against the Blue Jays in the American League Wild Card Series. He averaged 98.6 MPH on his four-seamer and sinker in that start, which was about 1.5 MPH more than his season average.

That increased velocity made him virtually unhittable. If he maintains these gains, we could expect another dominant outing, even against a formidable Astros offense. That gives Seattle an edge in what is essentially a must-win game in this best-of-five series.

The Astros will go with Valdez, who was a quality start machine throughout the season. The crafty lefty finished the year with a 2.82 ERA and 1.16 WHIP in 201.1 innings. However, he sputtered a bit down the stretch, giving up 13 runs (10 earned) in his last two outings in September.

While Valdez looked great in his final start of the season on Oct. 5, that was eight days prior to Game 2. That’s a lot of rest that could throw him off his routine. We’ve seen some rust from players with long layoffs so far, such as Justin Verlander in Game 1.

When you combine the pitching advantage, must-win situation, and rust factors, you come away thinking that the Mariners have a great chance at taking Game 2 and tying this series at 1-1 heading back to Seattle.

Mariners vs Astros Game 2 Best Bet

Mariners (+136) at FanDuel Sportsbook

WAGER: 1 Unit

I love the value on Seattle in this spot because of how dominant Castillo looked on the mound. He’s by far their best pitcher right now, so I think they get it done here, even after that heartbreaking loss in Game 1, where they blew a four-run lead.

Mariners vs Astros Game 2 Props

Luis Castillo Over 4.5 Strikeouts (-118) at FanDuel Sportsbook

I’ll roll with the Over on Castillo’s strikeout prop because I think he’ll be able to get there with volume. I’m projecting another deep outing of at least six innings for the Mariners ace.

PREVIOUS: Mariners vs Astros Game 1 Prediction

Astros 5, Mariners 1

The Astros put up a 112 wRC+ (6th), .176 ISO (4th), and 19.5% strikeout rate (2nd) this season. Not only does this offense have power, but they also make a lot of contact. In addition, they have tough hitters throughout the lineup, such as Jose Altuve, Kyle Tucker, Alex Bregman, and Yordan Alvarez.

Gilbert finished his season strong for Seattle, putting up a 2.00 ERA and 0.92 WHIP in 36 innings throughout September. This season, he pitched well against the Astros, posting a 2.52 ERA and 1.08 WHIP in 25 innings. However, we have to give the edge to Houston here.

The Astros will be rolling with the AL Cy Young favorite in Verlander. It was an incredible season for the future Hall-of-Famer, as he had an incredible 1.75 ERA and 0.83 WHIP in 175 innings. Verlander performed well against Seattle, with a 2.34 ERA and 0.92 WHIP in 42.1 innings.

Houston was dominant at home this season with a 55-26 record. They finished September by winning 22 of 31 games. As one of the World Series favorites, it’s hard to see them losing this game, especially with Verlander on the mound.

Mariners vs Astros Game 1 Best Bet

Under 6.5 Runs (+100) at FanDuel Sportsbook

WAGER: 1 Unit

While Houston has an elite offense, I feel more comfortable rolling with the Under, considering Verlander’s dominance this season. Add in that Gilbert comes in at top form, and this looks like the prudent play.

Mariners vs Astros Game 1 Props

Logan Gilbert Over 3.5 Strikeouts (-142) at FanDuel Sportsbook

This number is so low because of the Astros’ elite strikeout rate as a team, but Gilbert has been great throughout September, racking up 41 strikeouts in his last six starts, spanning 36 innings. While it’s pricey at -142 odds, you have to like the low bar here.


Frank Ammirante

Frank Ammirante is a Senior Sports Writer at The Game Day. Previously, he wrote for 4for4 Football and RotoBaller. Frank is a member of the Fantasy Sports Writer's Association while maintaining an active presence within the community. He has competed in industry contests like the Scott Fish Bowl, The Great Fantasy Baseball Invitational, and more. Frank will be making his debut in Tout Wars this year. He's got a diverse sporting background, but specializes in football and baseball.

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