Australian Open: Djokovic, Federer breeze into 4th round

Six-time Australian Open champion Djokovic continued his comeback from six months out with an injured right elbow, beating No. 21 Albert Ramos-Vinolas 6-2, 6-3, 6-3.

"I obviously have to be more humble this time with my expectations because I haven't played for six months," the 14th-seeded Djokovic said.

Federer entered the Australian Open last year under similar circumstances, coming off an extended break for a knee injury, and went on to win the title. His defence moved through another round with a 6-2, 7-5, 6-4 win over No. 29 Richard Gasquet.

Second-seeded Federer's next opponent is former world junior No. 1 Marton Fucsovics, who beat Nicolas Kicker in straight sets.

Djokovic will next face Hyeon Chung, who took out a Zverev for the second time this week. Chung beat fourth-seeded Alexander Zverev 5-7, 7-6 (3), 2-6, 6-3, 6-0 six days after a win over No. 32 Mischa Zverev in the first round.

Another unexpected loss at a major had the highly-touted Zverev admitted he may have a problem.

"Definitely not physical, so... I have some figuring out to do, what happens to me in deciding moments in Grand Slam," he said.

The 20-year-old Zverev has five titles on the elite tour but his fourth-round exit at Wimbledon last year remains his best run at a major.

Tomas Berdych ended 2009 U.S. Open champion Juan Martin del Potro's return to Melbourne Park for the first time since 2014 with a 6-3, 6-3, 6-2 win.

Halep fends off Davis

After wasting three chances to serve it out, then saving three match points, Simona Halep finally fended off American Lauren Davis in a third-round win that took 3 hours, 45 minutes and equalled a record at the Australian Open.

For top-ranked Halep, already playing with an injured left ankle, the 4-6, 6-4, 15-13 victory on Saturday was a testament to her renewed self-belief.

The third set took 2:22 and momentum swung, with 11 service breaks and two medical timeouts — for Davis to get treatment for toes on both feet — before Halep converted on her first match point.

Halep had chances to serve for the match in the 9th, 11th and 15th games of the third set but was broken each time by the No. 76-ranked Davis, who then blew three match points from 0-40 on Halep's serve in the 22nd game.

"Definitely was a very tough match, so long," said Halep, who has twice reached the final at the French Open but never won a Grand Slam singles title. "I never played the third set so long, so I'm really happy I could stay and win it. I'm almost dead."

It equalled the longest women's singles match at the Australian Open in terms of games played: Chanda Rubin's win over Arantxa Shanchez Vicario in 1996 was also 48 games. In terms of duration, it was almost an hour shorter than the record 4:44 that Francesca Schiavone needed to beat Svetlana Kuznetsova in 2011.

"I just feel that my muscles are gone," said Halep, who badly twisted her left ankle in the first round. "My ankle is, I don't know how it is because I don't feel it anymore! But ... it was nice to win this match."

Halep, who lost in the first round here in 2016 and last year, said she was mentally stronger now.

"I was down love-40. She had three match balls. It was not easy, but I just kept playing. I just kept believing that it's not over," Halep said. "For sure I'm stronger mentally, and I could resist like for every moment in the match. That makes me very happy, and I think the big win is that I could handle it."

Davis lost the three previous times she'd played in the third round of a major, but did everything possible to stay in the match, keeping long rallies alive to put pressure on Halep.

The 24-year-old American finished with roughly twice the number of winners (52 to 27) against slightly more than double the unforced errors (73-39), and broke Halep's serve six times.

"We were both fighting our hearts out. Every point was super long," Davis said. "I got to the point where I was so tired, I just told myself to swing and move. I didn't feel any pressure."

Halep will play Naomi Osaka in the next round.

Kerber dominates Sharapova

It was expected to be the match of the round. Angelique Kerber ensured it never became a contest.

The 2016 Australian Open winner routed Maria Sharapova 6-1, 6-3 in the third-round match on Saturday night, meaning she'll be the only Grand Slam champion in the fourth round of the women's draw.

Five-time major winner Sharapova was back at Melbourne Park for the first time since 2016, when a failed doping test led to a 15-month ban from tennis.

After two comfortable wins while seeded players fell in upsets in the first two rounds and was growing in confidence but had no answers for Kerber, who is on a 12-match winning streak in a kind of comeback of her own after a sliding down the rankings last year.

"I learned a lot from the last 12, 24 months. I had a great 2016 and last year was a little tougher," Kerber said, reflecting on how her year-end ranking dropped from No. 1 to 21 when she failed to defend her Australian or U.S. Open titles. "Anybody who knows me knows I never give up."

Sharapova said Kerber was the more aggressive on court, and took more risks.

"I gave her the confidence by making a lot of errors on the return games," Sharapova said. "She's a confident player at the moment.

"A lot of things I need to get better at and improve on. This is a process. It's a lot of things that take time.

"Today was not enough [but] ... looking at the overall picture, there's a lot to build from."

It was all over in one hour and four minutes.

Keys advances

U.S. Open finalist Madison Keys advanced 6-3, 6-4 over Ana Bogdan and will next play No. 8 Caroline Garcia, who beat Aliaksandra Sasnovich 6-3, 5-7, 6-2.

Sixth-seeded Karolina Pliskova had 11 aces and beat No. 29 Lucie Safarova 7-6 (6), 7-5 in a match featuring just one service break.

The 17th-seeded Keys, who lost in the U.S. Open final last year to Sloane Stephens, saved three break points serving for the match, finally clinching it on her first match point when Bogdan netted a backhand.

Keys missed last year's Australian Open after undergoing surgery to repair her injured left wrist. She then played only one match after the U.S. Open before shutting down her season early to let the wrist heal. It's helped her start the new season feeling mentally fresh, as well.

"I finished the U.S. Open and I was exhausted," she said. "So as amazing as that run was, the combination of being exhausted from that and having a wrist that still wasn't 100 per cent perfect, I just needed to kind of shut it down, calm down, and then I was really excited to start the new season."

On the men's side, fifth-seeded Dominic Thiem beat Adrian Mannarino 6-4, 6-2, 7-5 to move into the fourth round for a sixth consecutive major.