Top MLB Betting Picks for May 13: MLB Same-Game Parlays and Props
2026 Regular-Season Betting Record: 3-3-1 (-1.73 units)
2026 Regular-Season Player Props Betting Record: 1-6 (-5.11 units)
Two AL West rivals do battle in the third game of a four-game series Wednesday night, as Seattle continues its quest to ascend to the top of the division while Houston looks to begin reversing what's been a season-long swoon.
Without further ado, let's examine a same-game parlay and a player prop for tonight's game:
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MLB Picks for Mariners at Astros
- SGP: Mariners Alt Spread +1.5 and Over 4.5 Runs- F5 (+134 on FanDuel Sportsbook) for 1 Unit
- Randy Arozarena To Record 2+ Hits + Runs + RBI (-110 on FanDuel Sportsbook) for 1 Unit
Seattle Mariners at Houston Astros Best Bets
The Mariners have taken the first two games of the current four-game set against the Astros. They prevailed in a low-scoring pitcher's duel in the opener by a 3-1 margin before slugging their way to a 10-2 victory Tuesday on the strength of a nine-strikeout performance by Bryan Woo and 11 hits, including three extra-base knocks on the part of the blistering hot Randy Arozarena.
The results of the first half of the series extend a theme for both teams. While the Mariners appear to be building some momentum and are now just one game back of the Athletics in the AL West, the Astros are tied for last in the division with the Angels courtesy of an alarming 16-27 mark.
Houston has lost four straight and six of the last 10 overall, and their prospects for stopping the bleeding Wednesday aren't very bright. Lance McCullers will take the hill for Joe Espada's squad and checks into the night having pitched to a 9.39 ERA, 1.65 WHIP and 2.0 HR/9 across the 23.0 innings covering his last five starts. McCullers has surrendered at least six runs in three of those turns, and his impressive 9.4 K/9 in the sample is largely offset by a massive 6.3 BB/9. The veteran right-hander does appear to have run into some bad luck at times – he has an acceptable 4.50 xERA and .239 xBA, for example – but there's no getting around the fact he's also surrendering a 48.3% Hard-Hit% per Statcast, the second-highest figure of his career.
McCullers is also giving up some timely hits, having conceded a .286 average (including .333 with two outs) and .861 OPS to the 40 hitters he's faced with runners in scoring position. What's more, he's frequently run into trouble during the first half of games, pitching to ERAs of 6.43, 9.45, 6.00 and 14.54 in the first, third, fourth and fifth innings, respectively. He's also dealing with a tough opponent in the Mariners, whose current hitters have gotten to him for a collective .287 average, .811 OPS and seven extra-base hits across 91 career PA's.
McCullers' opposite number Bryce Miller Makes his first start of the season following his recovery from a left oblique strain. Miller put together a solid body of work in his ramp-up rehab assignment, especially in his final three appearances where he didn't allow a run over 12 innings while ringing up 12 Ks in that span.
Miller did have an uneven 2025 season that saw him pitch to a career-high 5.68 ERA and 1.41 WHIP. There could certainly be some rust in his first taste of big-league action while facing an Astros team that, despite its overall struggles, has scored the second-most runs in the AL (199) and ranks in the top 10 in baseball with 2.95 runs per first five innings per home game.
Given the numbers cited, our parlay focus on the Mariners remaining competitive at minimum over the first five frames and some runs being scored, likely on both sides. Then, Arozarena is sporting a .579 average over his last five games and has tagged McCullers for a .412 average and 1.033 OPS in 18 career encounters, putting a prop banking on him combining for at least two hits + runs + RBI very much in play in a game the Mariners carry a 4.8-run implied team total for.
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MLB Picks Recap
- SGP: Mariners Alt Spread +1.5 and Over 4.5 Runs- F5 (+134 on FanDuel Sportsbook) for 1 Unit
- Randy Arozarena To Record 2+ Hits + Runs + RBI (-110 on FanDuel Sportsbook) for 1 Unit
