Bernard Tomic's impressive resurgence has put the Australian two wins away from his first US Open main draw appearance in nine years.
The 32-year-old offered up moments of his awkward, disruptive best in a comprehensive 6-4 6-4 defeat of American Patrick Kypson on Wednesday (AEST).
One of six Australian winners on the day, Tomic next plays Portugal's Henrique Rocha after the world No.168 upset French veteran Pierre-Hugues Herbert in a lengthy three-set battle.
There are US Open concerns for Australian world No.79 Chris O'Connell, who retired after losing the first set to Roberto Bautista Agut at the lead-up event in Winston Salem.
The battling Aussie withdrew from last month's Toronto Masters with an oblique injury and then didn't play in Cincinnati, before attempting a return this week.
Tomic, the 2009 US Open junior champion hasn't featured in the Flushing Meadows main draw since 2017 and last played qualifying in 2018.
But Tomic, who climbed as high as world No.17 in 2016, has returned on a mission after aborting last week's delayed ATP Challenger final in Colombia to properly prepare for his main-draw shot.
The Barranquilla decider, delayed a day because of rain, was Tomic's second final at that level in the month and could have been his first major title since 2018.
Often criticised for a perceived lack of effort and intensity, Tomic has knuckled down in the last two years to surge from a career-low 835 to at least No.167 when the next rankings are calculated.
In June he took two top-100 scalps, including compatriot Rinky Hijikata.
A US Open berth would be Tomic's first grand slam main draw appearance since he qualified for the Australian Open in 2021.
Jason Kubler will meet Kyrian Jacquet in the second round after beating Brit George Loffhagen 6-4 7-5.
Australian women Olivia Gadecki, Priscilla Hon and Lizette Cabrera all won their first-round matches, while Destanee Aiava upset eighth seed Sara Bejlek, 6-4 4-6 6-4.
But Alex Bolt and Daria Saville both lost after four Australians had won first-round qualifying matches on Tuesday.
The qualifiers are hoping to join a dozen Australian direct entrants, led by men's world No.8 Alex de Minaur, and wildcards Tristan Skoolkate and Tahlia Gibson.
