Alexei Popyrin, Ajla Tomljanovic, Maya Joint into US Open second round as Popyrin-Djokovic showdown looms

Alexei Popyrin is refusing to let his mind wander after marching ominously ever closer to a blockbuster US Open showdown with defending champion Novak Djokovic.

Popyrin lived up to his star billing to be the first Australian winner on day one at Flushing Meadows before being joined in round two by exciting teenage prospect Maya Joint and 2022 women’s quarter-finalist Ajla Tomljanovic.

Popyrin cruised past Sonwoon Kwon without even hitting top gear, the recently crowned Montreal Masters champion eventually progressing with a 7-5 6-2 6-3 win in a tick over two hours.

Seeded for the first time at a slam, Popyrin crunched 14 aces, broke the South Korean six times while only dropping his own serve once all match.

Victory edged the 25-year-old to within one more win of a likely third-round Saturday night showstopper with the history-chasing Djokovic.

Popyrin next faces either unseeded Spaniard Pedro Martinez or Polish qualifier Maks Kasnikowski on Wednesday (Thursday AEST).

Chasing an unprecedented 25th singles major, Djokovic will open his campaign later on Monday (Tuesday AEST) as a prohibitive favourite to advance against Moldovan qualifier Radu Albot.

“I feel like I’ve had a lot of scenarios in my career where I had one more match, and then I would play a big match so I’ve kind of gotten used to focusing on the match that I’ve got in hand,” Popyrin said.

“And then if I win that, then, yeah, obviously I’ve got Novak in the third.

“But, honestly, I’m just thinking of this match and not thinking about Novak.”

The 28th-seeded Popyrin and 18-year-old Joint led the way as Australia’s bumper 20-strong contingent made a hot start to tennis’s final slam of the year.

The much-hyped Joint certainly didn’t disappoint on her grand slam main-draw debut, seeing off experienced German Laura Siegemund 6-4 7-5 to more than double her career on-court earnings in a single day.

The US-born talent overcame some second-set nerves trying to close out the most significant win of her career, letting a 5-0 lead and one match point slip at 4-5 on Siegemund’s serve.

Much to her joy and relief, Joint steadied to prevail on her fourth match point with a backhand volley winner.

Win or lose next up against American 14th seed Madison Keys, Joint will leave Flushing Meadows at least $US130,000 ($A192,000) richer for her efforts.

Two years after ending Serena Williams’ storied career on Arthur Ashe Stadium, Tomljanovic drew on the fond memories to also advance with a 6-4 6-4 win over American qualifier Ann Li.

But Kim Birrell bowed out with a 6-4 6-4 loss to Paris Olympics silver medallist Donna Vekic, the 24th seed.

Despite the defeat, Birrell will herself depart with a cheque for $US100,000 ($A147,575) - the biggest prize in tennis history for a first-round loser at a major.

Adam Walton was unable to follow Popyrin into the second round, succumbing 3-6 7-6 (9-7) 6-3 6-4 to French wildcard Alexandre Muller.

One of a record five Australian women’s qualifiers, Priscilla Hon has an exciting opportunity against world No.2 Aryna Sabalenka, the reigning back-to-back Australian Open champion in the feature women’s night match on Louis Armstrong Stadium.

Another 13 Australians play on day two, including 10th seed Alex de Minaur opening his campaign against American Marcos Giron.