Sebastian Korda stunned Daniil Medvedev to make a statement at the Australian Open 25 years after his father Petr claimed the title.
Melbourne Park has been a happy hunting ground for the family, with Sebastian winning the junior title five years ago, while his sisters Nelly and Jessica have both won the Australian Open in golf.
While it may be too soon to talk about the 22-year-old potentially adding more silverware, he was superb in a 7-6 (7) 6-3 7-6 (4) third-round victory over seventh seed Medvedev, the beaten finalist for the last two years.
The Russian has struggled for form since losing to Rafael Nadal from two sets up in the final 12 months ago and was simply outplayed by Korda, who began the season by reaching the final of the ATP event in Adelaide and pushing Novak Djokovic all the way.
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Medvedev hung on grimly in the first set, fighting back after dropping his serve three times, but Korda was always ahead in the tie-break.
The young American has a similar game to his opponent but he was doing everything better – striking his groundstrokes with precision, particularly off the backhand side, and coming to the net effectively.
He moved ahead early in sets two and three and, although he wobbled in sight of the finish line, he dominated a second tie-break to send another favourite packing following the exits of Nadal and Casper Ruud.
Earlier, Stefanos Tsitsipas, at three now the highest seed left, continued his serene progress through the draw to set up a rematch with Jannik Sinner.
He is yet to drop a set and defeated another in-form player in Dutchman Tallon Griekspoor 6-2 7-6 (5) 6-3.
Tsitsipas has made the semi-finals in three of the previous four years at Melbourne Park and is hoping to seize his chance of going further this time.
Mackenzie McDonald was unable to follow up his big victory over Nadal, struggling with an injury himself and resorting to underarm serves in a 7-6 (6) 6-3 6-2 loss to 31st seed Yoshihito Nishioka.
Sixth seed Felix Auger-Aliassime for once made a good start in a 6-1 3-6 6-1 6-4 victory over Francisco Cerundolo while 10th seed Hubert Hurkacz defeated Denis Shapovalov in five sets and Karen Khachanov saw off Frances Tiafoe.
Cameron Norrie’s hopes of reaching the fourth round of the Australian Open for the first time ended with a five-set loss to the Czech youngster Jiri Lehecka.
The British No 1 struggled initially in breezy conditions but looked to be on the right path when he opened up a two sets to one lead. But the 21-year-old Lehecka, ranked 71 in the world, battled back and Norrie took a medical timeout for treatment to his left knee early in the fifth set before falling to a 6-7 (8), 6-3, 3-6, 6-1, 6-4 defeat.