The 20-year-old is arguably the most exciting young talent in men’s tennis and his meeting with defending champion Federer tomorrow will be one to savour. But the young Greek also has a temper and, after the umpire decided to replay a set point for Tsitsipas during his clash with Nikoloz Basilashvili at 5-3 in the third set, the 14th seed let rip. Melbourne’s Greek population have turned out in numbers to support Tsitsipas and his countrywoman Maria Sakkari, and there were a lot of young fans in Margaret Court Arena. “It was heat of the moment. I said some really bad things,” said Tsitsipas after beating the dangerous Basilashvili 6-3 3-6 7-6 (7) 6-4. “I regret saying them. But I really wanted this really bad. “I didn’t quite think what I was saying. I wish I could change that and wouldn’t say that. It’s not the right attitude.” Tsitsipas was not born when Federer began his professional career but the 37-year-old continued to make top-level tennis look ridiculously easy in his 6-2 7-5 6-2 victory over young American Taylor Fritz. Rafael Nadal was equally impressive in a 6-1 6-2 6-4 victory over 19-year-old Alex de Minaur and next meets a resurgent Tomas Berdych, who recorded a 5-7 6-3 7-5 6-4 victory over 18th seed Diego Schwartzman. Grigor Dimitrov continued to take advantage of his favourable draw, beating Italian Thomas Fabbiano 7-6 (5) 6-4 6-4 to set up a last-16 meeting with America’s Frances Tiafoe. Roberto Bautista Agut continued his strong run by taking out 10th seed Karen Khachanov.