Former US Open champion Marin Cilic ended fifth seed Andrey Rublev's Australian Open campaign with an upset four-set victory to reach the fourth round on Saturday. The Croat, seeded 27, won 7-5, 7-6 (7/3), 3-6, 6-3 in a little over two-and-a-half hours on Margaret Court Arena to book a place in the last 16. It will be 33-year-old Cilic's eighth time in the fourth round at the Australian Open, where he was a beaten finalist to Roger Federer in 2018 after defeating Rafael Nadal in the last eight. Cilic will face Canada's ninth seed Felix Auger-Aliassime for a place in the quarter-finals. "I've had a good start to the season, played two weeks of tennis in Adelaide, and I've had two good matches here before this one," Cilic said. "The conditions in the evening were a bit cooler and allowed me to go more for my shots and I was really lining up a lot of them, especially the returns, it was really going well for me today. "I'm feeling really excited, I'm playing amazing and just looking forward to the next match, which gets tougher and tougher with the opponents, but I will try to give it my best." In all, Cilic landed 55 winners. It was also his second win in six meetings with Rublev, who reached the quarter-finals of last year's Australian Open. In the women's draw, Simona Halep eased past Danka Kovinic - conqueror of US Open champion Emma Raducanu - 6-2, 6-1 in just 64 minutes to set up a clash with Alize Cornet of France. Fit-again Halep came into the tournament full of confidence after her first title in 16 months earlier this month at a Melbourne warm-up event and was always in charge. The 14th seed next meets unseeded Cornet, who celebrated her 32nd birthday by slugging it out with Slovenian 29th seed Tamara Zidansek for a 4-6, 6-4, 6-2 victory. Meanwhile, world No1 Ash Barty will have to overcome the formidable Amanda Anisimova to keep alive her hopes of becoming the first Australian since 1978 to win their home Grand Slam when the two meet in the last 16 at Melbourne Park on Sunday. Barty and defending champion Naomi Osaka had been poised to meet in a heavyweight clash in the fourth round, but Anisimova edged out the four-time major winner to extend her winning streak to eight matches this year. The unseeded American could cause problems for Barty, who won their only previous meeting at the 2019 French Open but will be wary of Anisimova's power from the baseline, which was evident against Osaka as she fired 46 winners.