Mariners vs. Astros Prediction, Odds, Probable Pitchers and Prop Bets for Thursday, May 22

The Seattle Mariners open a four-game series against the Houston Astros on Thursday, May 22, at Daikin Park. Seattle, leading the AL West, aims to extend its division lead, while Houston looks to rebound after recent setbacks to their pitching rotation.

George Kirby is set to make his season debut for the Mariners after recovering from a shoulder injury that sidelined him for the start of the season. Kirby's exceptional command and low walk rates should bolster Seattle's rotation as he left off 2024 on a high note.

Lance McCullers Jr. gets the go for Houston, who has struggled in his return from injury, posting a 7.88 ERA and a 2.13 WHIP over 8 innings in 2025.

I’ll give my best bet for a player prop and break down analysis for a game prediction in this key AL West matchup.

Mariners vs. Astros Odds, Run Line and Total

Odds via FanDuel Sportsbook

Run Line

Mariners -1.5 (+116)
Astros +1.5 (-140)

Moneyline

Mariners (-132)
Astros (+112)

Total

Over 8.5 (-102)
Under 8.5 (-120)

Mariners vs. Astros Probable Pitchers

Mariners: George Kirby (0-0, 0.00 ERA)
Astros: Lance McCullers Jr. (0-1, 7.88 ERA)

Mariners vs. Astros How to Watch

Date: Thursday, May 22, 2025
Time: 8:10 p.m. ET
Venue: Daikin Park
How to Watch (TV): ROOTNW, Space City Home Network
Mariners Record: 28-20
Astros Record: 25-24

Mariners vs. Astros Best MLB Prop Bet

Lance McCullers Jr. Over 2.5 Walks (+115 at DraftKings)

McCullers Jr.’s woes through three starts have raised lingering questions on his command. He’s walking 3.96 batters per nine innings and I have to agree with SI’s Peter Dewey, who suggested he’s good to break 2.5 walks on Thursday in his latest MLB prop bets column.

Mariners vs. Astros Prediction and Pick

I said this last week when handicapping the Astros with McCullers Jr. on the mound and that’s that I can’t trust him with two entire years of rust since having last played.

He’s gotten out of two of his three starts without any earned runs barring the one nightmare against Cincinnati, but he holds an 8.74 xERA.

No thank you.

Who I am excited about is Kirby. The right-handed 27-year-old is making his season debut after having a lights-out end to the season that was capped off with an 8-1 victory over Houston with six strikeouts in six innings.

Although his rehab assignment numbers were average, he’s maintained his velocity from last season after recovering from shoulder inflammation. I’m looking for him to take advantage of an underperforming Astros lineup that’s without Yordan Alvarez, no less.

Pick: Mariners F5 (-142 at FanDuel)

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