The Houston Astros host the Seattle Mariners on May 12, 2026. First pitch from Daikin Park is scheduled for 8:10 p.m. EDT. The game will be broadcast on SCHN.
The Mariners are favored by -171 on the moneyline and by -1.5 on the run line. The Astros are +141 on the moneyline and +1.5 on the run line. The total is set at 8.5 runs.
Find my MLB picks and Mariners vs Astros prediction below, as well as probable pitchers, weather report, and more.
Mariners vs Astros Prediction
- Mariners vs Astros Pick: Tatsuya Imai Over 2.5 Walks Allowed (+144)
My Mariners vs Astros best bet is Tatsuya Imai Over 2.5 Walks. Make sure to find the best odds by checking our live MLB odds page.
Mariners vs Astros Odds
| Mariners Odds | ||
|---|---|---|
| Spread | Total | Moneyline |
-1.5 -105 | 8.5 -122o / 102u | -171 |
| Astros Odds | ||
|---|---|---|
| Spread | Total | Moneyline |
+1.5 -115 | 8.5 -122o / 102u | +141 |
- Mariners vs Astros moneyline: Mariners -171, Astros +141
- Mariners vs Astros over/under: 8.5 (-122 / +102)
- Mariners vs Astros spread: Mariners -1.5 (-105), Astros +1.5 (-115)
Mariners vs Astros Probable Pitchers
| RHP Bryan Woo (SEA) | Stat | RHP Tatsuya Imai (HOU) |
|---|---|---|
| 2-2 | W-L | 1-0 |
| 0.8 | fWAR (FanGraphs) | 0.1 |
| 4.02 / 3.55 | ERA / xERA | 7.27 / 3.82 |
| 3.80 / 4.32 | FIP / xFIP | 4.27 / 5.08 |
| 16.0% | K-BB% | 4.5% |
| 30.9% | GB% | 57.9% |
| .248 | BABIP | .368 |
| 109 | Stuff+ | 87 |
| 109 | Location+ | 97 |
Mariners vs Astros MLB Betting Preview
Seattle Mariners Betting Preview
The Mariners took game one of this series and will look to secure a series win tonight against the Astros. They have an intrinsic advantage with ace Bryan Woo on the mound, facing a struggling Tatsuya Imai in his return from the Injured List.
Woo's last start was a pristine six innings, with one hit, two walks, and zero runs allowed. However, he allowed 13 earned runs on six home runs combined in the two starts before then.
Bryan Woo has a track record from the past two seasons to give grace to a rocky two-start stretch. Tatsuya Imai does not. While Imai was touted as a big offseason addition for the Astros, there were significant concerns in his profile for the transition to a major league mound.
Houston Astros Betting Preview
Imai's start to his MLB career has been tumultuous. Imai's walk rate in the NPB was at least 9.5% in every year from 2018 to 2024. While it reached a career low of 7% in 2025, he also allowed at least 12% from 2019 to 2022.
Imai could not achieve a 20% K-BB until the 2025 season, when he was in his prime as a 27-year-old SP. His K-BB steadily improved from 2020 to 2025, but that does not say much for him as a prospect.
It remains to be seen whether the Astros were sold a lemon in a three-year, $54 million deal, but early returns are not promising.
Mariners vs Astros Pick, Betting Analysis
Tatsuya Imai has allowed at least three walks in every start since becoming a Houston Astros SP. He has allowed 11 walks in 8 2/3 major league innings and eight walks in five minor league innings.
His walk rate in the MLB and minors is above 20%. It is possible he really dealt with a "dead arm" that resulted in his IL stint and struggles thus far, but that could have been an excuse to shut him down for a bit.
Meanwhile, today's opponent, the Seattle Mariners, owns the seventh-best walk rate as a team against right-handed pitching. They've accomplished this despite losing leadoff man Brendan Dovonan for a chunk of the season.
Donovan and his career 9.4% walk rate against RHP returned this week and should contribute to a rough outing for Imai.
The obvious concern with today's play is Imai getting pulled early, but the Astros may require him to provide a semblance of length. Long relievers Cody Bolton and Kai-Wait Teng have thrown significant innings in the past two days.
Imai did not throw much in the minors to build up, but he did hit three innings in Triple-A, meaning a four or five-inning start is possible.
The Astros are not going to leave him out there to "die", but as the team continues evaluating him, they should allow him to pitch through any struggle and see how far he can go.
Pick: Tatsuya Imai Over 2.5 BB (+144)
