Still, it was Osaka who took the initiative early against Gauff, bookending the first set with breaks of serve. Though Gauff served admirably, striking just three double faults, she struggled off the ground, striking 16 unforced errors to Osaka’s five.
With Osaka serving first to start the second set, the pressure was on Gauff to keep in touching distance of the Japanese star, who won the first 15 first-serve points played through the first set and a half.
Opening the sixth game with a fifth double fault, Gauff framed a forehand to hand Osaka two chances to break. Osaka took full advantage, outrallying Gauff to move within two games of the finish line.
Having fallen just short of upsetting then-world No. 1 Iga Swiatek at 2024 Roland Garros, Osaka looked far more game to the challenge of knocking out a big name on a major stage, drawing more errors from Gauff to consolidate and take a 5-2 lead.
A netted forehand from Gauff helped Osaka flip a 40-15 deficit and earn her first match point. A final forehand miss took Osaka over the finish line.
Standing between Osaka and the semifinals will be either No. 11 seed Karolina Muchova (who has reached the last two US Open semifinals) and No. 27 seed Marta Kostyuk.
