US Open Tennis Predictions: Best Tennis Bets in Djokovic vs. Alcaraz, Sinner vs. Auger-Aliassime semifinals

The 2025 US Open continues in New York City on Friday, September 5 for Day 13 of the tournament and the men's semifinals at Flushing Meadows. The fourth and final Grand Slam of the year runs through to Championship Sunday on September 7 and as the tournament advances, we have the latest US Open best bets and tennis predictions.

The Dimers model has had a productive first half of the tournament, including a 2-0 day on our best High Value bets from Day 3 of the US Open, nailing Jannik Sinner as our top bet on Day 5 and another 2-0 result on Day 6 with bets on Carlos Alcaraz and Novak Djokovic and 2-0 again on Day 9 with Sinner and de Minaur before another 2-0 day on Tuesday and 2-0 again on Wednesday - that's a 6-0 run for the model right now!

As of this writing, we're just two matches away from hitting a +2500 pre-tournament outright on Anisimova and putting a cap on a profitable tournament.

Add in Dimers’ biggest betting offering ever—expanded markets, new bet types, and broader sportsbook coverage—and there’s never been a better time to bet on the US Open.

Best Value Bets for US Open Men's Semifinals - Friday, September 5

The Dimers model identifies spots where the sportsbooks have mispriced the odds, resulting in a betting opportunity with what we call an "edge." The best of these edges are deemed "High Value" bets and are the ones we're focusing on today:

Jannik Sinner -7.5 vs. Felix Auger-Aliassime

• Court: Arthur Ashe Stadium
• Time: 3:00 PM ET
• Win Probability: 65.4%
• Edge: 10.8%
• Best Odds: -120 (Caesars Sportsbook)

This is both our highest probability and best value play of the semifinals. Sinner has dropped just one set throughout this tournament and the Dimers model strongly backs him to keep his elite form en route to another championship appearance.

See our full match predictions for Sinner vs. Auger-Aliassime on Friday, including Moneyline and Game Totals.

Carlos Alcaraz vs. Novak Djokovic Under 37.5 Games

• Court: Arthur Ashe Stadium
• Time: 7:00 PM ET
• Win Probability: 58.0%
• Edge: 4.3%
• Best Odds: -1160 (FanDuel Sportsbook)

Carlos Alcaraz has come through time and time again this tournament for our model and is once again the focal point in this match. He'll face off against Novak Djokovic for the ninth time and the pair will now have faced off in every Grand Slam. Our model is strongly favoring the under with a slight lean towards Alcaraz on the game spread as well.

See our full match predictions for Sinner vs. Alcaraz-Djokovic on Friday.

To find value bets, including some moneyline upsets and more, check out Dimers' Best Tennis Bets every day of the US Open.

Betting the US Open Smartly

Dimers’ “High Value” picks provide bettors with calculated opportunities, but not every match comes with an edge. Keep an eye on our Best Tennis Bets section for all the latest value and picks.

With Flushing Meadows buzzing, the 2025 US Open is primed for drama, and Dimers is giving bettors every tool they need to play it smart.

Responsible Gambling

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