Hard-hitting Joint, one of only two teenagers in the WTA top 100 at a career-high No.53, struck one more winner than Tomljanovic, but delivered a wayward performance with 39 unforced errors to 18.
It was their second meeting within days after Tomljanovic retired due to illness just one set into their semi-finals in Morocco. Daria Kasatkina made it three Australian winners with a 6-1, 3-6, 6-2 dispatching of Czech Katerina Siniakova in her first grand slam for her adopted country.
Ajla Tomljanovic plays a forehand against Maya Joint.Credit: Getty Images
Popyrin lost in five sets to countryman Thanasi Kokkinakis last year despite leading 2-0 in the final set, following defeats to Aslan Karatsev, Fabio Fognini, 14-time champion Rafael Nadal, Lloyd Harris and Laslo Djere in previous years.
The Djere loss was the only one not in the first round, but Popyrin deserved to advance against Nishioka, who looked physically compromised early in the match and took a medical timeout after dropping the opening set.
Nishioka, who was ranked No.24 two years ago, has retired or handed his opponent a walkover at six of his past 10 tournaments, and also called it quits one game into the fifth set in the first round of last year’s US Open.
Popyrin has a good chance to go further, with another left-hander, Alejandro Tabilo, up next after the Chilean outlasted French wildcard Arthur Cazaux 5-7, 6-3, 6-2, 1-6, 6-3. Roland-Garros has mostly been a challenging tournament for Australians, outside Alex de Minaur’s surprise quarter-final run last year.
Maya Joint plays a forehand against Ajla Tomljanovic.Credit: Getty Images
“I can speak only on my behalf that I’m happy that I finally got a win here, [but] I think it’s not a secret that probably clay isn’t the best surface for Aussies,” Popyrin said.
“Slowly, we’re starting to see more and more results and more wins in the first round, which is great, both on the men’s and women’s side. Maya Joint just won a title on clay last week, which is massive for her.
“The clay court has not been our favourite, but ‘Demon’ [de Minaur] is playing unbelievable on the clay this year. Hopefully, I can make some results also.”
It was obvious from the outset that the contest was on Popyrin’s racquet. He boasts a 26-centimetre height advantage over Nishioka, and pounded 24 winners to 10 without facing a break point.
The hairiest it got for Popyrin was at 30-all in the sixth game of the second set, but he produced an excellent second serve then clobbered a big cross-court forehand that his Japanese rival could not retrieve.
The set was locked a point later before Nishioka dragged a forehand well wide to concede another break in the next game as Popyrin let out a guttural roar.
There was little explanation for Popyrin’s claycourt struggles in the French capital, given the surface has been his most successful by win percentage across his tour career.
He reached last month’s Monte-Carlo Masters quarter-finals – beating three top-20 opponents, including two-time Roland-Garros finalist Casper Ruud – and the same stage in Geneva last week.
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Popyrin would dearly love that form to continue because he is defending more than half his ranking points in the second half of the year, including his Masters 1000 title win in Montreal and third- and fourth-round showings at Wimbledon and the US Open, respectively.
He risks going into ranking freefall unless he can finish the season well after an injury-marred beginning to the year that included his co-coach Xavier Malisse ending their partnership at Indian Wells in March.
Popyrin is still working with Neville Godwin but has added another South African, Wayne Ferreira, to his team.
“I feel the most positive I felt leading up to a tournament in a long time. That’s very important for me,” he said.
“I think mentally it’s been challenging, but since the start of the claycourt [season], I feel like my game is starting to come back to me; the results are starting to show a little bit more, there’s more consistency and match wins every single week.”
Elsewhere, Jordan Thompson lost 6-4, 6-2, 6-1 to Czech Jiri Lehecka; Aleks Vukic went down 6-4, 6-4, 6-4 to Russian 24th seed Karen Khachanov; and Kim Birrell exited 6-1, 6-0 to Jaqueline Cristian.
Defending champions Carlos Alcaraz and Iga Swiatek headlined the day’s winners, but there were some major casualties, including Americans Emma Navarro and Taylor Fritz and Argentine Francisco Cerundolo.
No.10 seed Paula Badosa won her heavyweight battle with Naomi Osaka, 6-7 (1-7), 6-1, 6-4.
Watch all the Roland-Garros action on Stan live and on demand with no ads in play, starting Sunday night, May 25 from 7pm AEST.
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