Naomi Osaka passed her biggest test of the US Open to date on Monday, overcoming fellow youngster Aryna Sabalenka in three sets as spectators inside Louis Armstrong Stadium were treated to an enticing glimpse into the future of the WTA Tour.
Osaka and Sabalenka – two 20-year-olds through to the last 16 at Flushing Meadows for the first time - had each caught the eye during the opening rounds in New York.
The latter dropped just seven games across her first three matches, while Sabalenka displayed supreme ball-striking qualities to overpower Petra Kvitova 7-5 6-1.
Their fourth-round meeting was intriguing from the outset, but developed into a classic featuring several swings in momentum.
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And while Osaka ultimately prevailed 6-3 2-6 6-4, in a contest far removed from the cakewalks she had enjoyed in week one, both players appear highly likely to enjoy bright futures at the highest level.
With @Naomi_Osaka_’s win, this is the first time since 1995 Wimbledon there will be a Japanese male and female in the QFs of a Slam (alongside Nishikori).
— WTA Insider (@WTA_insider) September 3, 2018
1995 Wimbledon was the only time in the Open Era, so this is only the second time its happened in the Open Era.#USOpen
Osaka, of course, has already won a significant title, her shock triumph at Indian Wells earlier this year featuring straight-sets wins over Maria Sharapova, Karolina Pliskova and Simona Halep.
Sabalenka's maiden WTA crown was secured at New Haven in the week before this tournament, but there will surely be plenty more to come for her and Osaka.
In truth, they both demonstrated that they are not yet the finished product on Monday, mixing flashes of brilliance with sloppy spells. Nevertheless, they certainly provided rich entertainment.
Osaka, who won a remarkable 22 consecutive games to reach this stage, seized control early on, the Japanese demonstrating excellent defensive skills in response to Sabalenka’s appreciable power, before counter-punching superbly with perfectly timed aggression of her own.
Osaka’s ability to absorb Sabalenka’s power and then counter-punch is sublime.
— Chris Devine (@chrsdvn) September 3, 2018
The Japanese breaks to love to take the first set 6-3. Can Sabalenka cut out the errors and find a way back? #USOpen @OmnisportNews
It was noticeable that Osaka appeared more prepared to vary her play and find creative angles throughout the opening set, a policy that paid off as Sabalenka initially struggled to find her range and made too many unforced errors.
However, the Belarussian bounced back superbly and remained committed to going for her shots whenever possible as her opponent faded.
When an increasingly pumped Sabalenka broke for a 2-1 lead in the decider, victory looked set to come her way.
Yet Osaka – very much the favoured player for a crowd that increased significantly as the match wore on – got straight back on level terms and finished the stronger, ultimately sealing victory when her opponent double-faulted attempting to save a fourth match point.
Osaka, who wiped away tears of joy at the end of the contest, will now face an unseeded opponent in the last eight – either Marketa Vondrousova or Lesia Tsurenko – and is only three wins from following up her incredible Indian Wells success with an even bigger title.
Whatever happens in the remainder of this week, you get the feeling both she and Sabalenka will be gracing slam finals sooner rather than later.