Novak Djokovic will try to move within four matches of completing the first men's singles calendar-year Grand Slam in 52 years on Saturday when he faces Japan's Kei Nishikori at the US Open.
The 34-year-old Serbian star is 17-2 in the career rivalry with Nishikori and has beaten him 16 consecutive times entering their third-round matchup at Arthur Ashe Stadium.
"I'm very pleased with my level of tennis," Djokovic said. "All is going in the right direction."
With a fourth career US Open trophy, Djokovic would complete the first men's singles sweep of major titles in a single year since Rod Laver in 1969.
Top-ranked Djokovic also chases history in quest of his 21st career Grand Slam title, which would break the deadlock for the men's record he shares with Rafael Nadal and Roger Federer, both absent with injuries.
Djokovic, who briefly held all four Slam crowns at once after the 2016 French Open, most recently beat Nishikori in the Tokyo Olympic quarter-finals.
"I think it's important for me to serve well," Djokovic said. "I look forward to a good challenge."
Nishikori has not beaten Djokovic in seven years, since the 2014 US Open semi-finals, in which the Japanese star became the first Asian man to qualify for a Grand Slam final.
"I'm hoping every match," Nishikori said. "He's just tough player. I'm doing my best every match."
The Djokovic-Nishikori winner faces a Monday matchup in the fourth round against either 99th-ranked US wildcard Jenson Brooksby or Russian 21st seed Aslan Karatsev.
While he has never played Brooksby, Djokovic is 1-1 against Karatsev, beating him in this year's Australian Open semi-finals before losing to him on clay in the Belgrade semi-finals.
Canadian sixth seed Bianca Andreescu, the 2019 US Open champion, advanced to the last 16 by defeating 104th-ranked Belgian lucky loser Greet Minnen 6-1, 6-2.
"I'm very happy with my performance," Andreescu said. "For me to perform like this on this kind of stage it's an honor."
Andreescu will next face the winner of a later match between Czech 10th seed Petra Kvitova, a two-time Wimbledon champion, and Greek 17th seed Maria Sakkari.
Andreescu is part of a Canadian charge at the US Open that has seen teen compatriot Leylah Fernandez oust four-time Grand Slam champion Naomi Osaka and Felix Auger-Aliassime join Fernandez in the fourth round with seventh seed denis Shapovalov hoping to join them.
"It's truly amazing," Andreescu said. "I'm super grateful to be a part of that group."
Night matches on Ashe include world number one Ashleigh Barty of Australia, the reigning Wimbledon champion, against American Shelby Rogers and Tokyo Olympic champion Alexander Zverev, the fourth seed from Germany and 2020 US Open runner-up, against 184th-ranked US wildcard Jack Sock.
Barty is 5-0 all-time against Rogers, four of the wins coming this year.
Sock has a 2-1 edge over Zverev in their career rivalry, winning in 2016 at Stockholm and 2017 at the ATP Finals while losing their first matchup in 2016 at Beijing.
With a victory, Sock would be the lowest-ranked man into the US Open last 16 since 187th-ranked Ken Flach in 1987.