Naomi Osaka, Novak Djokovic advance to U.S. Open quarters

Naomi Osaka, Novak Djokovic advance to U.S. Open quarters

Australian tennis player John Millman, now ranked 55th in the world, just knocked Roger Federer out of the US Open.

In women's action, Naomi Osaka became the first Japanese woman to reach the quarterfinals of a Grand Slam in 14 years, edging Aryna Sabalenka 6-3, 2-6, 6-4 in a matchup of 20-year-olds.

Before this year's US Open, Millman had only ever progressed past the first round of a Grand Slam tournament on a handful of occasions, with his previous best efforts coming in third round exits at the 2016 Australian Open and 2016 Wimbledon.

"I think we both struggled a little bit with the heat, but we both played good tennis".

"I've got a lot of respect for Roger".

"I felt like a deer in the headlights to begin with, to be honest", he said.

Before the match, Federer said he was "a big fan of John", having trained with him in the past. Very rarely do you find Roger on defence, his anticipation, his ability to go cross court and not recover to the middle of the court is a major advantage.

Millman cursed himself for missing one set point but threw everything into a series of forehands to bring up a second and forced Federer into another error.

" I'm not 21 any more".

"You have a team to get you ready, but sometimes you just have to survive".

The victor of the Djokovic-Millman quarter-final will play seventh-seeded 2014 champion Marin Cilic or Japanese star Kei Nishikori for a spot in Sunday's title match.

Nishikori will next face either seventh seed Marin Cilic, which will be a rematch of the 2014 final, or Belgian 10th seed David Goffin.

Millman, ranked 55 in the world, capitalised on some sloppy serving from an under-par Federer to secure victory with the time approaching 1am in NY and move into a quarter-final clash with another former US Open victor, Novak Djokovic.

"I'm really looking forward to making the most of a second week at a grand slam", he said.

The first Portuguese player to reach the fourth round of any Grand Slam, the 68th ranked Sousa never looked a threat to progress any further as his magical U.S. Open run came to an end.

Kohlschreiber was denied again in his fifth attempt to win a fourth-round match at the US Open.