Coco Gauff extended her perfect start into the second week of the Australian Open with a straight-sets win over Leylah Fernandez on Friday.

The American world No. 3 player and one of the favorites to win the Melbourne title easily defeated the No. 30 seed from Canada 6-4, 6-2 in the third round at Rod Laver Arena.

Gauff, who has yet to drop a set in eight matches this season, won all five singles matches in the season-opening Fed Cup, including a 6-3, 6-2 victory over Fernandez, the pair's previous match. The only confrontation.

"I think it's more difficult because she knows what's going to happen, and I definitely think she performed differently today than she did in the Fed Cup," said Gauff, who is now on a 12-game winning streak.

"Lyla is a great competitor, great player, great person, so I knew today was going to be a tough game regardless of the outcome a few weeks ago."

Gauff, the 2023 US Open champion, lost to Aryna Sabalenka in the Australian Open semifinals last year in her best performance at Melbourne Park to date.

This year she is expected to compete with the world's number one and double defending champion.

Before that, the 20-year-old will face Belinda Bencic, who advanced after Naomi Osaka pulled out injured, for a place in the quarter-finals.

Fernandez, ranked 29th in the world and a defeated finalist at the 2021 US Open, reached the third round in Melbourne for the first time and found Gauff's accuracy difficult to deal with.

The American stepped up the gas midway through the first set, breaking Fernandez's serve.

A double break at the start of the second set put Gauff in control, but at 3-0 on serve, she made two double faults, giving Fernandez a break opportunity and a glimmer of hope.

If Fernandez felt the door open, Gauff would immediately slam it shut and score again, 4-1.

With the score at 5-2, Gauff hit two searing backhand winners - one from the baseline, one from across the line - and sealed it with an irreversible lob in 1 hour and 16 minutes won the victory

Gauff pays attention to Bencic after Osaka retires

Gauff will now face Swiss Bencic, who advanced to the last 16 after two-time champion Naomi Osaka retired in the third round on Friday.

Bencic won the first set 7-6(3) in a tie-break before Japan's Osaka, who had withdrawn from the Auckland final earlier this month with the same abdominal injury, withdrew from the tournament.

Osaka said the results of her pre-match MRI scan were "not ideal" but she still made it through two rounds, defeating Caroline Garcia and Karolina Muchova in three sets.

But the clash with Bencic, who was ranked 294th in the world at the start of the Open, proved to be too much for the 27-year-old, who said her withdrawal appeared to be " inevitable". Early rounds.

"It's not great, I'm not feeling good, I'm not feeling bad. Somewhere in the middle," Osaka told reporters.

"It's been a little hectic trying to manage it (during the tournament) because obviously I've had a really tough draw. But we're also doing the best we can. I'm getting treatment every day and into the evening. So the days are long for me. Obviously , it got worse after my last game.”

Bencic broke serve early to take a 1-0 lead, but Osaka showed promise and quickly found her range, keeping the Swiss at bay with effective first serves and deep groundstrokes, while also making crucial holds. Serving maintained his courage and led 5-2.

But Osaka, who won the title at Melbourne Park in 2019 and 2021, clearly struggled, losing her cool when she failed to complete a serve, while Bencic grew in confidence with two searing catches.

Osaka then called a physical therapist during a line change, and although she initially persisted after treatment, she was unable to continue after the tie-break.

"I really feel for Naomi, I saw her struggling a little bit at the end of the set and obviously that's not the way you want this match to end," Bencic said.

"I thought it was a good game, so hopefully she'll be better soon and be able to play well the rest of the season."