Thanasi Kokkinakis won’t be the only male flying the flag for Australia in the Sydney International, with two local qualifiers winning through to the main draw.

Matthew Barton and Christopher O’Connell ensured there would be a strong local flavour at the Australian Open warm-up event at Homebush with strong victories on Sunday’s opening day.

With David Cup captain Lleyton Hewitt in the stands on show court one, world No.196 Barton served strongly in a 6-3 6-1 win over Mathias Bourgue.

Then world No.237 O’Connell made it a five-man contingent after toppling Spaniard Enrique Lopez-Perez 6-3 7-5.

The pair join Kokkinakis, Jordan Thompson and Alex De Minaur in a weak field that boasts just one top-20 player in world No.8 Dominic Thiem.

Sydney-born Barton made headlines last year after progressing to the second round at Wimbledon in the 25-year-old’s grand-slam debut.

The 18-year-old O’Connell will make his first senior appearance in his home town.

At least one Australian will progress to the second round. Thompson and Kokkinakis, who will play together on Sunday night in the Brisbane International doubles final, are set to face off in round one in Sydney.

The match will be the 20-year-old Kokkinakis’ first on the tour after a shoulder injury had limited the promising talent to a single Olympics match in 2016.

Top-seeded Thiem said it was important to get as much court time as he could after being losing in the quarter-finals of the season-opening Brisbane event.

“It worked out well a few times for me, that I played in the week before the slam, especially last year before the French Open,” Thiem said on Sunday.

“Last week, Brisbane was a very strong field but I only got two matches so it’s perfect here to get used to the conditions. Here, it’s very hot which (it) can also be in Melbourne.”