Australian Open 2021: Rafael Nadal, Jessica Pegula, Ash Barty Top Monday Results

Rafael Nadal cruised into the quarterfinals of the 2021 Australian Open on Monday.

The Spaniard triumphed in straight sets against Fabio Fognini to headline a mostly unsurprising set of results on the men's side of the bracket.

Meanwhile, Jessica Pegula's remarkable run at the tournament continued. The American's three-set triumph over Elina Svitolina provided the most notable result of the day for the women as she advanced to the final eight.

Australian Open Results

Men

(2) Rafael Nadal def. (16) Fabio Fognini; 6-3, 6-4, 6-2
(4) Daniil Medvedev def. Mackenzie McDonald; 6-4, 6-2, 6-3
(5) Stefanos Tsitsipas def. (9) Matteo Berrettini; walkover
(7) Andrey Rublev def. (24) Casper Ruud; 6-2, 7-6 (3), ret.

Women

(1) Ashleigh Barty def. Shelby Rogers; 6-3, 6-4
Jessica Pegula def. (5) Elina Svitolina; 6-4, 3-6, 6-3
(25) Karolina Muchova def. (18) Elise Mertens; 7-6 (5), 7-5
(22) Jennifer Brady def. (28) Donna Vekic; 6-1, 7-5

Only two of the four matches on the men's side were actually played to completion, and both were straight-set romps. Nadal faced little resistance in rolling over Fognini, while Daniil Medvedev ended Mackenzie McDonald's surprising run to the fourth round.

Stefanos Tsitsipas and Andrey Rublev both advanced when their opponents were unable to physically compete. 

Nadal is seeking to become the first man in the Open era to win every Grand Slam at least twice, and he said he remains motivated to push forward:

"I play tennis. I like tennis. I like what I am doing. That's the main thing. Of course, I am very motivated to win Grand Slams and to play in the most important events of the year. No doubt about that… [But] I have never been obsessed [with] trying to be the best. I just do [it] my way. That’s worked for me.

"I think ambition is important, to have an ambition, but a healthy ambition. If you have too much ambition, then you can be frustrated when you are not able to achieve all the things that you wanted. I never approached the sport and my career that way."

Pegula defeated Svitolina 6-4, 3-6, 6-3 in the day's only three-set match in the women's bracket. The 26-year-old American had never advanced past the third round of a major before this current run, which has seen her defeat two-time Australian Open champion Victoria Azarenka and Svitolina, who both came in thinking they could win the year's first major.

No matter what happens, at least one American will be making the semifinals. Pegula will take on countrywoman Jennifer Brady in the quarterfinals. Brady earned a straight-sets win over Donna Vekic in her fourth-round matchup. 

"It's an opportunity for both of us," Pegula told reporters. "I'm just happy I'm here; she's been playing some good tennis, solidifying herself as a top player."

Serena Williams is set to play Tuesday night against Simona Halep, which could lead to two of the four semifinalists being American—Naomi Osaka grew up in the United States but relinquished her citizenship in 2019 to play for Japan in the Olympics.

Top-seeded Ashleigh Barty ended the chances of three American women being in the semis with her straight-sets win over Shelby Rogers. Barty will move on to play Karolina Muchova.