Marta Kostyuk takes on American Sloane Stephens in the second round of the 2026 US Open on Wednesday.
Kostyuk has had a consistent, strong season, while Stephens, once No. 3 in the world, is outside the top 200 in the WTA rankings.
Find my US Open preview and Kostyuk vs Stephens prediction for Wednesday below.
Marta Kostyuk vs Sloane Stephens Player Prediction
- Kostyuk vs Stephens Pick: Sloane Stephens to Win a Set (+162, bet365)
My Kostyuk vs Stephens best bet is on Stephens to win a set. Make sure to find the best odds by checking our live ATP odds page.
Kostyuk vs Stephens Odds
| Marta Kostyuk Odds | -1040 |
| Sloane Stephens Odds | +599 |
| Spread | Kostyuk -5.5 (-135), Stephens +5.5 (-110) |
| Over/Under | 18.5 (-165o / +105u) |
| Kostyuk-Stephens H2H | 1-0 |
| Time | How to Watch | Wednesday, Approx. 1 p.m. ET | ESPN |
| Odds via DraftKings | |
Kostyuk vs Stephens Predictions, Betting Analysis
By: Tudor Cosma
Kostyuk is one of the best in the world right now, as she reached the semifinals at both Roland Garros and Wimbledon in 2026.
She shows few weaknesses, is a great athlete and her serve is real weapon.
Meanwhile, Stephens played excellently in her first match at the US Open, a short victory over Clara Tauson.
She's in her best form in recent years, and I believe there's an opportunity for her to take a set, even though it's very unlikely she'll upset Kostyuk.
With the line currently at +162 at bet365, I think there's value on taking Stephens, who's playing on Louis Armstrong in front of a home crowd.
Pick: Sloane Stephens to Win a Set (+162, bet365)
