MELBOURNE, Australia -- -- As Daniil Medvedev sat courtside trying to rehydrate during a changeover, an image of nine-time Australian Open champion Novak Djokovic flashed up in the stadium behind him.
It was in the third set Saturday, and it was like the absent No. 1 was looking over the shoulder of the player who is effectively the No. 1 seed at the year's first Grand Slam tournament.
Medvedev, who lost last year's Australian Open final to Djokovic but avenged that with a victory over the Serb for the U.S. Open title, reached the fourth round for the fourth straight year at Melbourne Park with a 6-4, 6-4, 6-2 win over Botic van de Zandschulp.
Medvedev, 25, was a conspicuous fan favorite on Margaret Court Arena, too, two days after being unsettled by the boos and jeers of a parochial crowd on Rod Laver Arena when he ended the run of mercurial Australian Nick Kyrgios.
He was critical of a lack of respect in that match -- mostly about the noise between first and second serves -- and this time offered some relationship advice to the crowd.
"Every good relationship must have its ups and downs," he said in his on-court TV interview, explaining that he planned to be back on court quite often in the future. "I hope it's going to be more good times than bad times, otherwise it doesn't work."
Medvedev, who is from Russia, later clarified he didn't have a problem with the Australian crowds and had been fully expecting to have them against him when he played Kyrgios -- just not while he was in his service motion.
"The other night I was playing against an Australian player, very electric Australian player," he said. "After the match, I think it was, yeah, straightaway pretty actually fun for everybody.
"That's how I felt, and I didn't see actually a lot of let's say negative reactions."
Medvedev avoided a showdown with Djokovic after the world's top-ranked player had his visa canceled and was deported on the eve of the tournament for failing to meet Australia's strict COVID-19 vaccination criteria.
He also avoided another match against an Australian in the fourth round when wild-card entry Chris O'Connell lost to Maxime Cressy 6-2, 6-7 (6), 6-3, 6-2.
Cressy's win means there are two 24-year-old Americans who'll be in the fourth round of a major for their first time.
No. 70-ranked Cressy is in his fourth Grand Slam tournament. No. 20-ranked Taylor Fritz finally made it in his 22nd attempt, with a 6-0, 3-6, 3-6, 6-4, 6-3 win over No. 15 Roberto Bautista Agut, and said it "means a ton."
"I mean, it's huge. Like after that match I was almost close to like tearing up a bit," Fritz said. "It seems stupid, because so many people have made the second week of Slams but it's just, like, eluded me for so long.
"I never doubted it would happen," he added, "but I definitely, definitely was getting sick of playing, you know, Top 4 player for the opportunity every time."
Fritz will next play fourth-seeded Stefanos Tsitsipas, a runner-up at the French Open and semifinalist in Australia last year, who fended off Benoit Paire 6-3, 7-5, 6-7 (2), 6-4.
Former US Open champion Marin Cilic upset No. 5-seeded Andrey Rublev to reach the fourth round.
The 33-year-old Cilic, who won the 2014 U.S. Open title and was a runner-up to Roger Federer in Australia in 2018, beat Rublev 7-5, 7-6 (3), 3-6, 6-3 in the last match completed on Day 6 of the year's first Grand Slam tournament.
He went into the encounter with just one win in his previous 15 matches against Top 10 players and had lost his previous four head-to-heads against Rublev, but was dominant from the start.
Cilic will next play No. 9 Felix Auger-Aliassime, who won 14 of the last 16 games in his 6-4, 6-1, 6-1 third-round win over No. 24 Dan Evans.
The Associated Press contributed to this report.