Last season, the Seattle Mariners left it late, as they trailed the Houston Astros in the AL West standings for much of the season before finally surpassing them in September and going on to finish one game away from their first World Series appearance. In 2026, Seattle looks locked in for another prolonged battle, as it currently holds just a half-game lead over the Texas Rangers and has only a 63.3% chance of winning the division, the third-lowest odds of any current division leader.
The Mariners will hope to put more space between themselves and the Rangers as they play the middle game of a three-game set against the bottom-feeding Cincinnati Reds tonight at 9:40 p.m. ET. First pitch is scheduled for 9:40 p.m. ET.
It should be a star-studded pitching matchup, as Cincinnati will start newly-extended Chase Burns and Luis Castillo will toe the rubber for Seattle.
Let’s break down this clash with some odds and lines at DraftKings Sportsbook.
Cincinnati Reds at Seattle Mariners Best Bets
- Cincinnati Reds Moneyline (+101): This is the third matchup today in which I’ve gone for the underdog on the Moneyline, but Burns is so much better than Castillo that it should nullify the Mariners’ home-field advantage.
- Over 2.5 Home Runs (+100): There aren’t typically many homers at T-Mobile Park, baseball’s most pitcher-friendly venue, but both of these pitchers are prone to give up the occasional long ball, and both of these offenses have plenty of pop.
Cincinnati Reds at Seattle Mariners prediction, preview
For a while, the entire NL Central was over .500, but the Reds fell below that mark on June 5 and have remained there ever since. They’ve had a particularly rough go of it since the start of June, going just 15-26 across that span, including an 8-0 loss in the series opener last night. Cincinnati is tied for the 10th-lowest OPS in baseball this season, as while rookie Sal Stewart, Elly De La Cruz, and JJ Bleday have been bright spots, free agency signing Eugenio Suárez has been a disaster, posting just an 82 OPS+. Additionally, the Reds have had the league’s sixth-worst bullpen, as they haven’t had much depth beyond Brock Burke and Tejay Antone. Even Cincinnati’s rotation has been a bottom-10 unit despite Burns’ All-Star campaign, as Brady Singer and Rhett Lowder haven’t provided much support. The Reds will be one team to watch at the trade deadline, as they could conceivably buy for the future or sell current assets.
Seattle is trending in the opposite direction. The Mariners were below .500 for most of the season, falling to 25-29 on May 24, but they rattled off eight straight wins and have spent most of the last two months within a few games of that mark. Surprisingly, Seattle’s offense has been a disaster, ranking fourth-to-last in OPS. Last season’s MVP runner-up Cal Raleigh has been horrific, battling injuries and slashing .163/.266/.307, and as good as Randy Arozarena has been, Julio Rodríguez has had the worst offensive season of his career and free agency signing Brendan Donovan has played just 25 games. The Mariners have made up for it by having the fourth-best rotation, which has been buoyed by Emerson Hancock’s breakout. Additionally, Seattle’s bullpen has been the fourth-best in baseball, as Eduard Bazardo, Jose A. Ferrer, and Gabe Speier all have sub-3 ERA’s. Closer Andrés Muñoz, after a slow start to the season, also hasn’t given up a run since June 14, tossing 12 scoreless innings since then. The Mariners will definitely be buyers at the trade deadline.
Thankfully for Cincinnati, Burns has lived up to his immense potential this season, making the All-Star team and pitching to a 2.54 ERA across 18 starts. While he ended the first half on a bit of a rough note, giving up 10 earned runs in 17.0 innings across his final three games before the All-Star break, that shouldn’t take away from his tremendous season overall, as he gave up two or fewer earned runs in 14 of his first 15 starts. Advanced stats back up his impressive resume: he ranks in the top sextile in expected ERA, expected batting average, fastball velocity, chase rate, whiff rate, and strikeout rate. The latter three should further exacerbate Seattle’s offensive issues, as it has chased, whiffed, and struck out at among the league’s highest frequencies. However, Burns has had some issues with hard hits, ranking in just the 27th percentile in barrel rate, and the Mariners rank near the league average in barrel rate despite their offensive struggles overall. Additionally, the splits are against Burns; he has been slightly worse on the road, and despite T-Mobile Park’s status as baseball’s most pitcher-friendly, Seattle’s offense has been slightly better at home.
Castillo, meanwhile, hasn’t had a great season. Though he was a Cy Young Award vote-getter as recently as 2023 and had a solid 3.54 ERA last season, he’s struggled in 2026, posting a 4.93 mark through 18 appearances (15 starts) as the clear weak link in the Mariners’ rotation. He’s been in particularly poor form lately, giving up at least four earned runs in two of his last four appearances, and while a few outliers contribute to much of the damage, he’s only had two scoreless outings. Advanced numbers don’t paint a very positive picture of him, as he ranks below the 40th percentile in all but three Statcast categories and has just 98 Stuff+. Castillo’s impressive chase and walk rates should be an asset against a pretty disciplined Reds team, but his bottom-quartile barrel rate, hard-hit rate, and average exit velocity could be problematic, especially since Cincinnati records barrels at the second-highest clip. To make matters worse, he’s been significantly worse at home this season, and the Reds’ offense has been remarkably consistent whether at home or on the road.
Cincinnati Reds at Seattle Mariners pick, best bet
Best Bet: Cincinnati Reds Moneyline (+101)
Despite his rough last few starts of the first half, Burns is a much better pitcher than Castillo, and as long as he can avoid giving up too many barrels, his strengths should further exacerbate Seattle’s weaknesses. Cincinnati should be well-suited to get to Castillo.
Strong Lean: Over 2.5 Home Runs (+100)
Burns is prone to giving up the occasional long ball, conceding one in 11 of his 18 starts, and Castillo just allowed three against the Tampa Bay Rays in his most recent start. Both of these teams rank in the league’s top half in home runs.
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