Young Stefanos Tsitsipas signalled a changing of the guard at the top of world tennis as he shocked defending champion Roger Federer in the Australian Open fourth round Sunday.

The 20-year-old NextGen Finals champion beat Federer, who is 17 years his senior, 6-7 (11-13), 7-6 (7/3), 7-5, 7-6 (7/5) on Rod Laver Arena.

Tsitsipas, seeded 14, became the first Greek in history to reach the quarter-finals of a Slam where he will meet Spain's 22nd seed Roberto Bautista Agut.

The Swiss had 12 breaks points that slipped through his grasp as his hopes of a 21st Grand Slam title were ended with Tsitsipas becoming the first Greek to ever reach the quarter-finals of a major tournament.


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