MELBOURNE, Australia (AP) — Rafael Nadal was awake at 1 a.m., engrossed in Roger Federer's third-round match at the Australian Open.

The top-ranked Nadal explained, after beating fellow Spaniard Pablo Carreno Busta 6-1, 6-2, 6-4 on a warm Saturday afternoon, how he couldn't sleep until after Federer had clinched a fifth-set super tiebreaker by winning the last six points to beat Australian John Millman the previous night.

Federer was able to fight his way through to the second week on a day when 23-time major winner Serena Williams, defending women's champion Naomi Osaka and 2018 winner Caroline Wozniacki all made surprising third-round exits.

There was more to follow in a chaotic third round on Saturday, with women's No. 2 Karolina Pliskova and No. 6 Belinda Bencic also upset in straight sets.

For Nadal, the key was to keep things simple. He hadn't lost to a fellow Spaniard since his first-round shocker here against Fernando Verdasco in 2016. That was the only time since 2006 that he hasn't reached the quarterfinals or better at Melbourne Park, where he won the title in 2009 and has reached four finals since.

“My best match of the tournament so far without a doubt — a very positive thing. Super happy," Nadal said. “Sorry for Pablo, he’s a good friend of mine. (But) for me, it’s great news I’m in the fourth round."

Nadal changed into a bright pink cap and jacket after the match, accessorizing his pink shoes. A fan held up a sign telling Rafa he was "perfect in pink.

Against Carreno Busta, he hit 42 winners and made just 18 unforced errors. He didn't face a break point and didn't serve any double-faults.

“It’s true that when the conditions are a little bit warmer, the bounces are a bit higher, the ball is flying, it helps my game," Nadal said. “Today I did very well with my serve — I started to hit some very good forehands down the line. That’s a key shot for me."

He acknowledged to the crowd at Rod Laver Arena that he'd watched the Federer-Millman encounter, saying the see-sawing on-court emotions kept him gripped.

He'll be watching a night match involving another Australian on Saturday, too, when Nick Kyrgios takes on 16th-seeded Karen Khachanov of Russia on Melbourne Arena.

Nadal and Kyrgios are unfriendly rivals — there's been animosity on both side — but the 19-time major winner doesn't buy into hype.

“Both players are great players. Nick always is excited to play here at home. Karen is a player with great potential,” he said. “I’m going to enjoy watching.”

One fourth-round meeting is already set, with 10th-seeded Gael Monfils advancing 7-6 (2), 6-4, 6-3 over No. 256-ranked Ernests Gulbis to a match against fifth-seeded Dominic Thiem, who beat American Taylor Fritz 6-2, 6-4, 6-7 (5), 6-4. No. 17 Andrey Rublev ousted No. 11 David Goffin 2-6, 7-6 (3), 6-4, 7-6 (4).

Two highly-ranked women who bucked the trend of upsets were Wimbledon champion Simona Halep and three-time major winner Angelique Kerber. Each said they'd learned to keep their heads down when there are clusters of upsets and ignore any big names dropping.

“I’m not focusing on other players — just focusing on myself,” Halep said after her 6-1, 6-4 win over Yulia Putintseva on Rod Laver Arena, the match after Pliskova lost to 7-6 (4), 7-6 (3) to 30th-seeded Anastasia Pavlyuchenkova. “It doesn’t matter who is winning, who is losing, I just have to do my job when I step on to court.”

Kerber had 6-2, 6-7 (4), 6-3 win over Camila Giorgi. In a later news conference, she almost laughed when asked if nervousness was contagious in the locker room when the top players start exiting.

“Every match starts from zero — doesn't matter who against you play," she said. “You have sometimes a little bit bad days, good days. So it's more about caring yourself, working on your strengths and going for it. So it's nothing about looking around."

The left-handed Kerber next faces Pavlyuchenkova, who was a junior champion here 12 years ago when she beat Caroline Wozniacki in the final. They're playing for a spot in the quarterfinals, a stage Pavlyuchekova has reached five times but never surpassed at the majors.

Having a bunch of top players missing from the second week doesn't come into Pavlyuchekova's thinking, either.

“I don’t focus so much on names any more. I’ve been on the tour for a while," she said, when asked about the absence of Williams, Osaka and so on. "Those are really big names and great players, but it’s tennis. Nowadays, as you can see, surprises happen. I just try not to lose myself and be in the present, do what I have. I have the next match to play Angelique — why should I care about all the other names?"

Bencic, a semifinalist at the U.S. Open last September, was rolled 6-0, 6-1 in 49 minutes by 28th-seeded Anett Kontaveit, who will next play Iga Swiatek, the No. 59-ranked player from Poland who took out 19th-seeded Donna Vekic 7-5, 6-3.

A day after upsetting Osaka in the singles, 15-year-old Coco Gauff combined with Caty McNally for a win in the second round of women's doubles. The American teenagers beat eighth-seeded pair Kveta Peschke and Demi Schuurs 6-3, 6-4.

___

More AP Tennis: https://apnews.com/apf-Tennis and https://twitter.com/AP_Sports