The Mariners head to Houston at 20-22 — not great, but a damn sight better than what the Astros (16-26) have been doing. Houston has dropped 4 of their last 5 and the season series against Seattle is a clean 5-0 sweep so far. That is not a typo. The Astros have not beaten the Mariners in 2026.
Bryan Woo gets the ball coming off his best start of the year — 6 scoreless against Atlanta with 9 strikeouts and a single hit allowed. That outing pulled his line back to 2-2 with a 4.02 ERA after a rough April stretch where he got tagged for 7 earned by the Cardinals and 6 more by the Royals. The version of Woo from May 7 is a problem; the version from late April is not.
On the other side, Tatsuya Imai is being reinstated from the 15-day IL to make this start, and the audit on him is ugly. The arm-fatigue absence stretched more than a month, his rehab work produced 8 walks in 5 innings, and his last MLB appearance was the one-out disaster against this same Mariners lineup with 4 walks and a hit batter. A 7.27 ERA is the number on the page. The control is the actual concern.
The market has Seattle at -141 on the moneyline and -1.5 on the runline, which feels light given the matchup. Both sides carry slightly negative EV, but the public is hammering the Mariners — 71% of moneyline bets and 65% of the handle on Seattle. The total sits at 8.5, and if Imai can't find the zone early, the over plays itself before the bullpens even warm up.
The injury sheets are doing both teams no favors. Seattle is rolling without Bryce Miller (returns Wednesday), Matt Brash, Gabe Speier, Victor Robles, and Patrick Wisdom. Houston is somehow worse off — Carlos Correa just had ankle surgery, Jeremy Pena is on a rehab assignment, Yainer Diaz is out, Jake Meyers is out, Hunter Brown is on the 60-day, and Josh Hader is still rehabbing in Triple-A. Imai walking back into that rotation tonight is less a return and more a rescue.
- Day-To-DayTeddy McGraw SP — McGraw is working his way back from right elbow issues, Jonathan Mayo of MLB Pipeline reports.
- 10-Day-ILPatrick Wisdom 1B — The Mariners placed Wisdom on the 10-day injured list Friday due to a left oblique strain, retroactive to Wednesday.
- 10-Day-ILVictor Robles RF — Robles (pectoral) will begin a rehab assignment at Triple-A Tacoma on Sunday, Adam Jude of The Seattle Times reports.
- 10-Day-ILWill Wilson 3B — The Mariners placed Wilson on the 10-day injured list Saturday due to a fractured left thumb.
- 15-Day-ILMatt Brash RP — Brash (lat) will throw a bullpen session Monday, Shannon Drayer of SeattleSports.com reports.
- paternityJose Ferrer RP — The Mariners placed Ferrer on the paternity leave list Monday.
- 15-Day-ILBryce Miller SP — Miller (oblique) will return from the injured list to start Wednesday's game against the Astros, Shannon Drayer of SeattleSports.com reports
- 15-Day-ILGabe Speier RP — The Mariners placed Speier on the 15-day injured list Monday with left shoulder inflammation, Ryan Divish of The Seattle Times reports.
- Day-To-DayLance McCullers Jr. SP — McCullers was removed from his start Wednesday against the Dodgers in the top of the third inning after he appeared to be contending with a blister on his pitching hand, Chandler Rome of The Athletic reports. He was charged with six earned runs on four hits and three walks over 2.2 innings prior to his departure.
- Day-To-DayWalker Janek C — Double-A Corpus Christi placed Janek on its 7-day injured list Sunday due to an unspecified injury.
- Day-To-DayLucas Spence OF — Double-A Corpus Christi placed Spence on its 7-day injured list April 22 due to an unspecified injury.
- 10-Day-ILJeremy Pena SS — Pena (hamstring) will begin a rehab assignment Tuesday, likely at Double-A Corpus Christi, Brian McTaggart of MLB.com reports.
- 10-Day-ILJake Meyers CF — Meyers (oblique) is slated to begin a rehab assignment this week, Matt Kawahara of the Houston Chronicle reports.
- 10-Day-ILCarlos Correa SS — Correa is scheduled to undergo surgery Monday in Houston to repair the tendon in his left ankle, Brian McTaggart of MLB.com reports.
- 10-Day-ILJoey Loperfido LF — The Astros announced Monday that Loperfido (quadriceps) has started light running and light baseball activity, Matt Kawahara of the Houston Chronicle reports.
- 10-Day-ILTaylor Trammell CF — The Astros announced Monday that Trammell (groin) has begun a running progression in addition to taking part in light baseball activity, Matt Kawahara of the Houston Chronicle reports.
Bottom line: the Mariners have every structural advantage here. Better starter, better recent form against this specific opponent, and an Astros team that can't get healthy and can't get a win against them. If Seattle drops this one, it's a story. If they take it, it's just Tuesday.