MLB Same Game Parlays & Picks: Monday (8/31)
The last day of August is here, and I’m offering my two best MLB same-game parlays (SGPs) after narrowly missing two cashes last week, going 2-1 on each three-leg SGP.
The Mariners continued their narrative as one of MLB’s most disappointing teams with another series loss to the Blue Jays, and I expect their struggles to continue against a strong American League contender in the Red Sox. I also look at what should be a high-scoring affair in the White Sox-Astros tilt, and support that SGP with two player props.
Let’s dive into the two best MLB SGPs for Monday, August 31st.
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Monday’s Best MLB Same Game Parlays
(Odds courtesy of DraftKings Sportsbook)
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Seattle Mariners vs. Boston Red Sox
- Leg 1: Red Sox Moneyline (-171)
- Leg 2: Payton Tolle Over 17.5 Outs Recorded (-128)
- Leg 3: Willson Contreras 1+ Hits (-190)
Teams have seemingly been loading up their left-handed pitchers to start against the Mariners of late, and that usually turns out to be a winning proposition. Seattle ranks dead last in the Majors in batting average on balls in play (BABIP) against southpaws. And the Mariners are certainly not hitting for power when they do put the ball in play, owning the league’s worst slugging rate in that split.
Those are big reasons why I expect a long outing from Payton Tolle, especially since he has gone over this projected total in four out of five August starts, and six out of eight overall. But I also do not fully trust in George Kirby’s ability to match zeros, even though he rebounded nicely from a 7.13 ERA and .327 opponent’s average in five starts prior to his last outing. In that span, he also had three starts with five or more earned runs and fewer than five innings pitched. Kirby’s 97.9 miles per hour (MPH) average velocity on his fastball was his fastest average velocity in a start during his career, but time will tell if he matches that in this road start.
Based on Kirby’s lofty .327 opponents’ average in a recent five-start stretch, I add a more conservative third leg of Willson Contreras to record a hit, which he has done in 10 of the last 16 games, with four multi-hit games mixed in.
Parlay Odds: +331
Chicago White Sox vs. Houston Astros
- Leg 1: Over 8.5 Runs (-104)
- Leg 2: Yordan Alvarez 1+ RBI (+141)
- Leg 3: Andrew Benintendi 1+ Hits (-163)
Astros righty Peter Lambert is coming off tying a career-high with nine earned runs in his last start. I expect the struggles to continue against the power-hitting White Sox even though he had allowed two or fewer earned runs in his previous eight starts.
Yordan Alvarez hit his American League-leading 37th home run on Saturday, snapping a 12-game home run drought. While that drought was one shy of his season high, he still batted in runs in five other games in that span.
Andrew Benintendi by year as a White Sox:
2023: 45 RBI | .356 SLG | 88 OPS+
2024: 64 RBI | .396 SLG | 94 OPS+
2025: 63 RBI | .431 SLG | 104 OPS+
2026: 69 RBI | .438 SLG | 109 OPS+He's improved every year he's been with Chicago! 🧦 pic.twitter.com/OKUJWoKDXd
— Just Baseball (@JustBB_Media) August 30, 2026
Saturday was also a big day for Andrew Benintendi, leading the team to victory with a three-hit day. His hits were the only ones the team produced in the win, and they improved his slash line to .351/.407/.632 with 14 home runs and 40 RBI in 46 career games at Target Field. While the opponent is different today, his continued improvement makes him a solid addition to this SGP.
Parlay Odds: +663
Mike Spector is a featured writer at BettingPros. For more from Mike, check out his archive and follow him @MikeSpector01.