MELBOURNE, Australia — An hour after his win, Andy Murray still hadn't been able to get any video to see how he twisted his ankle and tumbled to the ground.

There's a good chance the most-viewed clip by that stage at the Australian Open was of the between-the-legs shot by enigmatic local hope Nick Kyrgios late Wednesday in his surprising loss to Andreas Seppi in the second round.

The third day of the season-opening Grand Slam had gone generally to script until the evening.

Roger Federer's progress was straight-forward, beating 20-year-old qualifier Noah Rubin 7-5, 6-3, 7-6 (3) to maintain his record of never failing to reach the third round at the 18 Australian Opens he's contested.

After back-to-back wins over qualifiers, the 17-time Grand Slam champion's comeback from a six-month injury layoff will increase in the degree of difficulty. Next up, Federer faces 2010 Wimbledon finalist Tomas Berdych, who had a 6-3, 7-6 (6), 6-2 win over Ryan Harrison.

Also looming, potentially, is No. 5 Kei Nishikori, the 2014 U.S. Open finalist.

They're all in the top-heavy quarter of the draw with the top-ranked Murray, who for a few moments at least was wondering if he'd make it to the third round.

Murray's shoe caught on the surface and he tumbled to the court at Rod Laver Arena, clutching his right ankle and cringing in pain during the third game of the third set against No. 156-ranked Andrey Rublev.

The five-time Australian Open runner-up continued and won that game, but told himself, loudly, "It's not good news." He saw a trainer during the next change of ends, but decided he didn't need any extra treatment on his already heavily braced joint.

He limped and stretched for a while, but went on to win 6-3, 6-0, 6-2.

"I was moving OK toward the end," he said, "so that's positive."

Speaking at a midnight news conference, Murray mentioned that his ankle had throbbed during the match and he hadn't been able to see the replay to determine the cause.

"It just a little bit stiff just now," he said, but "I don't think I've done too much damage."

It was Murray's 178th win in a Grand Slam match, joining Stefan Edberg in a tie for eighth on the list of match winners in the Open era.

Murray next faces No. 31 Sam Querrey, who had 7-6 (5), 6-0, 6-1 win over 17-year-old wild-card entry Alex De Minaur.

U.S. Open champion Stan Wawrinka, who won his first major title in Melbourne in 2014, advanced 6-3, 6-4, 6-4 over Steve Johnson and will next play No. 29 Viktor Troicki in the lower quarter of the draw's top half.

That part of the draw is now missing No. 7 Marin Cilic and the 14th-seeded Kyrgios, who were beaten in night matches.

Cilic, the 2014 U.S. Open champion, lost in four sets to Daniel Evans. Seppi, ranked 89th, rallied from two sets down and saved a match point to beat Kyrgios 1-6, 6-7 (1), 6-4, 6-2, 10-8 in a seesawing match that featured that oddly-time 'tweener.

Seppi was serving for the match when Kyrgios, already one of the most analyzed athletes in Australia, changed the pace of a rally with the high-risk shot that will spark further debate about his attitude toward the game.

He won the point, and that game, but 32-year-old Seppi kept his cool and won the match, closing with an ace.

"Yeah, it's obviously disappointing," said Kyrgios, returning from a suspension over his performance in Shanghai last year. "But it was ultimately a pretty fun match. He's a great guy and he deserved it, so ... I'm not going to beat myself up about it."

No. 19 John Isner, the highest-seeded American in the men's draw, lost to Mischa Zverev 6-7 (4), 6-7 (4), 6-4, 7-6 (7), 9-7. But wins by No. 23 Jack Sock and Querrey ended the day on a more positive note for the Americans.

Defending champion Angelique Kerber celebrated her 29th birthday with a 6-2, 6-7 (3), 6-2 second-round win over Carina Witthoeft.

The crowd sang "Happy Birthday," but Kerber wasn't entirely in tune on the court. The No. 1-ranked German angrily swiped her racket in the second set in a burst of frustration that momentarily threw her off her game.

Also, French Open champion Garbine Muguruza beat Samantha Crawford 7-5, 6-4 in a night match, while Venus Williams had a 6-3, 6-2 win over Stefanie Voegele and later withdrew from the doubles — she was scheduled to partner her sister, Serena.