Mariners vs Astros Betting Guide – 5/22/25

Seattle Mariners

@

Houston Astros

The Seattle Mariners visit Minute Maid Park for the first game of their series against the Houston Astros on May 22, 2025. The Mariners come into this matchup with a solid record of 28-20, riding the momentum of their recent victory over the Astros, where they prevailed 6-5 on May 21. The Astros, struggling with a 25-24 record, are looking to bounce back after suffering an 8-4 loss in that same game.

On the mound, the Mariners will send George Kirby, who has been a standout performer this season, ranking as the 26th best starting pitcher in MLB according to advanced statistics. Kirby has shown remarkable consistency, posting an impressive 1 earned run and 6 strikeouts in his last start. Conversely, Lance McCullers Jr. will take the hill for the Astros. Unfortunately for Houston, McCullers has struggled, currently holding a 7.88 ERA and ranking as the 138th best starting pitcher. His high walk rate of 15.6% could be problematic as he faces a Mariners offense known for its plate discipline and ability to draw walks, sitting 2nd in MLB in that category.

Offensively, the Mariners rank 10th overall, bolstered by their 6th best home run total in the league. In contrast, the Astros’ offense ranks only 18th, with a particularly concerning 21st rank in home runs. This series opener sees the Mariners favored with a moneyline of -135, reflecting confidence in their potent lineup and Kirby’s strong form.

According to projections, the Astros may have some struggle to generate runs, with an average implied team total of 3.77 runs, while the Mariners are projected at 4.23. As the season progresses, this matchup could define the trajectory for both teams, especially as the Mariners aim to solidify their standing in the American League West.

Seattle Mariners Insights

• George Kirby – Over/Under 4.5 Strikeouts (+125/-160)
  Among all starters, George Kirby’s fastball velocity of 96 mph ranks in the 88th percentile since the start of last season.
  Explain: Velocity is a key component to fastball success in generating strikeouts and preventing runs.
• Dylan Moore – Over/Under 0.5 Total Bases (-120/-110)
  Dylan Moore has been cold recently, with his seasonal exit velocity of 85-mph dropping to 81-mph in the past 14 days.
  Explain: Hitting the ball hard increases the chances of either a home run or the ball landing in fair territory for a hit before a fielder can get to it.
• Cal Raleigh – Over/Under 1.5 Total Bases (+125/-165)
  Cal Raleigh pulls many of his flyballs (42.2% — 99th percentile) and has the misfortune of hitting them towards the game’s 9th-deepest RF fences today.
  Explain: This player’s skill set does not match up particularly well with the park he’s in today, which may lead to worse-than-usual performance.

Houston Astros Insights

• Lance McCullers Jr. – Over/Under 4.5 Strikeouts (-115/-115)
  Considering that groundball batters have a big edge over flyball pitchers, Lance McCullers Jr. and his 47.3% underlying GB% (according to the leading projection system, THE BAT) will be in a difficult spot in this matchup matching up with 3 opposing GB bats.
  Explain: This mostly has to do with the way the hitter’s swing plane interacts with the pitch trajectory, and it can create diminished performance across all categories and hidden value few are considering.
• Victor Caratini – Over/Under 0.5 Total Bases (-150/+120)
  Extreme flyball bats like Victor Caratini tend to be less successful against extreme flyball pitchers like George Kirby.
  Explain: This mostly has to do with the way the hitter’s swing plane interacts with the pitch trajectory, and it can create diminished performance across all categories and hidden value few are considering.
• The Houston Astros (20.3 K% (according to the leading projection system, THE BAT X) project to have the 3rd-least strikeout-prone batting order of all teams on the slate today.
  Explain: THE BAT X analyzes each player in today’s specific lineup to figure out which teams have the least inherent strikeout potential for the opposing pitcher.

Betting Trends

• Houston Astros – Over/Under 1.5 1st Five Innings (F5) Team Total (-135/+105)
  The Houston Astros have hit the 1st Five Innings (F5) Team Total Under in 7 of their last 8 games (+6.40 Units / 64% ROI)
• Seattle Mariners – Moneyline (-130)
  The Seattle Mariners have hit the Moneyline in 11 of their last 14 away games (+9.30 Units / 54% ROI)
• Victor Caratini – Over/Under 0.5 Home Runs (+800/-1900)
  Victor Caratini has hit the Home Runs Over in 2 of his last 5 games at home (+12.40 Units / 248% ROI)