Mariners vs Astros Prediction, Pick, Odds for Monday, September 23

The Seattle Mariners are making a late charge up the standings as we round out the final month of the season, sitting two games out of the wild card and five back of the Houston Astros in the AL West. Now, the division rivals will do battle in what promises to be one of the more meaningful series of the month.

With Bryce Miller entering on a torrid run, does Seattle have a shot at grabbing a crucial game to kick off the final week of the season, or will he be outdone by the talented Hunter Brown?

Let's break down the best way to bet on Mariners vs. Astros on Monday night.

Mariners-Astros Prediction

• Mariners-Astros pick: Over 7.5 (-120 | Play to Over 8 -110)

My Mariners vs Astros best bet is on Over 7.5, where I see value at -120. The best line is available at BetMGM, as well as other sportsbooks — make sure to find the best odds by checking our live MLB odds page.

Monday, Sep 23

8:10 p.m. ET

SCHN

Mariners Odds
Spread	Total	Moneyline
+1.5 -185	7.5 -118o / -102u	+110

Astros Odds
Spread	Total	Moneyline
-1.5 +154	7.5 -118o / -102u	-130

Odds via DraftKings. Get up-to-the-minute MLB odds here.

Kenny Ducey’s Mariners vs Astros Preview

Seattle Mariners Betting Preview: Just a Hair of Good Luck

It's been quite the month for Miller, who owns a 1.99 ERA in four September outings heading into this one. He's allowed just 14 hits and two home runs in 22-2/3 innings, posting a beefy 26.1% strikeout rate along the way. His Expected Batting Average for the month stands at .244, however, signaling just a hair of good luck, and he's also struggled with control to the tune of a 10.2% walk rate.

That's a big deal, considering Miller has been excellent all year in limiting walks, and he's also pitched above his xBA for the year, which sits at .234. He's pitched to slightly more contact on the ground as well with a lower launch angle this month, perhaps leading to the influx of expected hits.

As for this offense, it has somehow continued to produce with the third-highest wRC+ in the league over the last two weeks. Strikeouts are still a concern, though not nearly as much as they were earlier in the year, with 23.5% of Seattle's plate appearances ending in a third strike, but this team's done an excellent job of drawing walks and has coupled a .272 average with a decent-enough .160 Isolated Power. It seems the Mariners are finally abandoning their all-or-nothing approach at the dish.

Houston Astros Betting Preview: Tough Month in a Breakout Season

Unlike Miller, Brown's had a tough month as he comes down the stretch of what's been a breakout 2024 season. He's been good enough with a 3.71 ERA in three starts, throwing 12 innings of two-run ball around a five-inning nightmare against the A's that saw him surrender five runs on nine hits.

The strikeouts were at least flowing for Brown until he ran into a very patient Padres team, but in those outings, his xBA has come in at .316 with a disastrous .495 Expected Slugging. He'll be hoping to pick things back up against a Mariners side that's improved in that department but is still striking out far too much, and while the numbers above look menacing, the matchup against a team that's hit for more average is a friendlier one considering the batting average against him has been higher than expected, while he's pitched beneath his xSLG.

This offense has been a bit of a mixed bag, enduring some brutal series lately but still standing eighth in wRC+ over the last 14 days. Houston's had a contact-heavy approach just as it has all year, hitting .282 with an extremely-low 15.2% strikeout rate, but walks have continued to be hard to come by.

Mariners vs Astros Prediction, Betting Analysis

The Astros present an issue for Miller as a team that has done an excellent job of making contact, even if they've left a lot to be desired in terms of drawing walks. This one should be a contact-fest, with Brown's brutal month continuing against a Mariners team that's been populating the bases with runners.

With that, I'm going to back both offenses in this one.

I'm not overly confident that either of these teams will be able to hit for power, but with a number this low and oddsmakers anticipating a pitcher's duel, I think we've got a clear way in here. Expect both teams to continue putting the ball in play against two arms that, by the hit probabilities, have been full of issues over their last few starts.

Pick: Over 7.5 (-120), BetMGM

Moneyline

The Mariners opened up as +140 underdogs on Sunday afternoon, but some action on Seattle has steadily pushed them down to +130 as of this writing. They reached as low as +125 late Sunday. We've tracked some sharp action and big money coming in on Seattle.

Run Line (Spread)

The Astros have hit the run line in eight of their last 11 games and rank sixth in baseball with a 47.1% cover rate as home favorites. Seattle, meanwhile, has the third-worst record in the league against the run line as underdogs.

Over/Under

Each of these teams has seen the over cash in their last three games, and while the Astros have played to the over in just 42.4% of their games, the best spot to take that bet has been when they're favored in Houston with a 49.3% hit rate.

• 95% of the bets and 80% of the money are on the Astros moneyline.
• 94% of the bets and 100% of the money are on the Astros to cover the run line.
• 85% of the bets and 79% of the money are on the over.

Mariners Betting Trends

• Mariners are 3-2 in their last 5 games.
• Mariners are 3-2 in their last 5 games against the spread.
• Mariners are 33-45 in their road games against the spread.
• The totals have gone OVER in 3 of Mariners' last 5 games.
• The totals have gone OVER in 29 of Mariners' last 78 games at home.

Astros Betting Trends

• Astros are 3-2 in their last 5 games.
• Astros are 3-2 in their last 5 games against the spread.
• Astros are 39-39 in their road games against the spread.
• The totals have gone OVER in 3 of the Astros' last 5 games.
• The totals have gone OVER in 36 of the Astros' 78 last games at home.