A quick look at the Australian Open:

LOOKAHEAD TO TUESDAY:

Milos Raonic's perfect record at Melbourne Park this year — four straight-sets victories, including a third-round win over No. 6 Stefanos Tsitsipas — is in for a serious quarterfinal test against a guy he's never beaten in nine attempts. That would be defending champion Novak Djokovic. Raonic has made a strong start to the year after missing a good portion of play in 2019 with knee, hamstring and back issues. The former world No. 3's ranking blew out to 35 because of his injury troubles. But he's back in fine form, particularly in the biggest part of his game. He's won 59 games in a row on his serve. “Milos is one of the tallest, strongest players on tour and has one of the biggest serves,” Djokovic said. “I’ve got to be ready for missiles coming from his side of the net. One key element will be how well I’m returning." Raonic has been to the quarterfinals here five times, but only advanced to the semis once, when he lost to Andy Murray in five sets in 2016. If he gets to the final four this year he'll have to beat the seven-time champion at Melbourne Park. "I'm going to have to serve well clearly, and then I think I'm going to have to get my return at a high percentage," he said. "I think we play quite opposite from each other, and he's done a good job in the past neutralizing my serve." In the other quarterfinal, third-seeded Roger Federer takes on 100th-ranked Tennys Sandgren. Federer barely made it through his third-round match against John Millman, needing six consecutive points in the fifth-set super tiebreaker, then dropped the first set of his four-round match before advancing. Ash Barty and Petra Kvitova will play a women's quarterfinal for the second consecutive year in Melbourne. Last year when Kvitova was seeded eighth, she beat No. 15 Barty in straight sets. This year Barty is No. 1 after winning the French Open and WTA Finals and having a stellar 2019. “I love Petra, let's hope she doesn't break my heart." Barty said. In the other women's quarterfinal, 14th-seeded Sophia Kenin plays unseeded Ons Jabeur.

Serbia's Novak Djokovic celebrates after defeating Diego Schwartzman of Argentina in their fourth round singles match at the Australian Open tennis championship in Melbourne, Australia, Sunday, Jan. 26, 2020. (AP PhotoAndy Wong)

Serbia's Novak Djokovic celebrates after defeating Diego Schwartzman of Argentina in their fourth round singles match at the Australian Open tennis championship in Melbourne, Australia, Sunday, Jan. 26, 2020. (AP PhotoAndy Wong)

TUESDAY'S FORECAST

Mostly sunny, high of 23 Celsius (73 Fahrenheit)

MONDAY'S WEATHER

Sunny, high of 23 C (73 F)

MONDAY'S KEY RESULTS

Men's fourth round: No. 1 Rafael Nadal beat No. 23 Nick Kyrgios 6-3, 3-6, 7-6 (6), 7-6 (4); No. 5 Dominic Thiem beat No. 10 Gael Monfils 6-2, 6-4, 6-4.; No. 7 Alexander Zverev beat No. 17 Andrey Rublev 6-4, 6-4, 6-4; No. 15- Stan Wawrinka beat No. 4 Daniil Medvedev 6-2, 2-6, 4-6, 7-6 (2), 6-2.

Australia's Ashleigh Barty celebrates after defeating Alison Riske of the U.S. during their fourth round singles match at the Australian Open tennis championship in Melbourne, Australia, Sunday, Jan. 26, 2020. (AP PhotoAndy Wong)

Australia's Ashleigh Barty celebrates after defeating Alison Riske of the U.S. during their fourth round singles match at the Australian Open tennis championship in Melbourne, Australia, Sunday, Jan. 26, 2020. (AP PhotoAndy Wong)

Women's fourth round: No. 4 Simona Halep beat No. 16 Elise Mertens 6-4, 6-4; Garbiñe Muguruza beat No. 9 Kiki Bertens 6-3, 6-3; No. 28 Anett Kontaveit beat Iga Switek 6-7 (4), 7-5, 7-5; No. 30 Anastasia Pavlyuchenkova beat No. 17 Angelique Kerber 6-7 (5), 7-6 (4), 6-2

STAT OF THE DAY: 41: The number of times Rafael Nadal has reached the quarterfinals at a Grand Slam tournament, moving him equal with Jimmy Connors in third place and behind only Roger Federer (57) and Novak Djokovic (46).

QUOTE OF THE DAY: “When he is playing like today, with this positive attitude, he gives a lot of positive things to our sport. So I encourage him to keep working like this. Honestly, he is one of the highest talents that we have on our tour.” Nadal speaking about the mercurial Nick Kyrgios after their fourth-round match.

Petra Kvitova of the Czech Republic waves after defeating Greece's Maria Sakkari in their fourth round singles match at the Australian Open tennis championship in Melbourne, Australia, Sunday, Jan. 26, 2020. (AP PhotoAndy Wong)

Petra Kvitova of the Czech Republic waves after defeating Greece's Maria Sakkari in their fourth round singles match at the Australian Open tennis championship in Melbourne, Australia, Sunday, Jan. 26, 2020. (AP PhotoAndy Wong)

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