Thanasi Kokkinakis defeats Stan Wawrinka at French Open as ...

Thanasi Kokkinakis has roared to the biggest win of his career, battling to an epic, exhausting landmark five-set victory over former champion Stan Wawrinka at the French Open.

Key points:Kokkinakis reached the third round of the French Open as a teenager in 2015Injury has since hampered the Australian, who is currently ranked number 108 in the worldFellow Australians Storm Hunter and Jason Kubler both bowed out of the French Open

Kokkinakis had waited for eight long injury-scarred years to reach the third round of another grand slam after reaching the last-32 at Roland Garros as a teenager and tumbled emotionally into the red clay at finally repeating the dose with his monumental effort on Wednesday.

On a gusty, clay-blown Court Simonne Mathieu, faced by a packed house all cheering for the Swiss favourite, Kokkinakis eventually broke the dogged 2015 champion, winning 3-6, 7-5, 6-3, 6-7 (4-7), 6-3.

The Adelaide went a huge way to exorcising some agonising near-misses this year, headed by his near six-hour loss to Andy Murray at the Australian Open.

He even had to go through the agony of Wawrinka saving four match points from 40-0 down in the final game before sealing the win on serve.

"What a match. I knew Stan's getting older but the first set-and-a-half he was playing the best tennis he could play. I was nowhere, just tried to hang in there," Kokkinakis told the crowd.

"I lost that match against Murray, I didn't want to do it against another legend.

"Having 40-0, I was like, 'oh no', you can imagine the things coming into my mind. He just never went away — but I just trusted myself, and I'm so happy."

Nick Kyrgios, who had once famously taunted Wawrinka during a match in Montreal by telling him that his friend Kokkinakis had once slept with the Swiss's girlfriend, had built this contest up as a real "popcorn match" — and he wasn't wrong as a breathtaking, see-saw four hour 38 minute contest unfolded.

It was the perfect pick-me-up for the Aussie challenge after Storm Hunter's chance of a breakthrough triumph on the same court over Ukraine's comeback star Elina Svitolina had blown out after a dazzling start, 2-6, 6-3, 6-1.

And Hunter's fellow Queenslander Jason Kubler also departed in the second round, beaten by the swashbuckling Italian Fabio Fognini 6-4, 7-6 (7-5), 6-2.

It looked as if Kokkinakis also might find 38-year-old Wawrinka too hot to handle in the battle between two warriors finding fresh life in their careers after being put through the injury mill.

Wawrinka, not slowed by a five-set opening win against Albert Ramos-Vinolas, strutted into a one-set, 4-2 lead but Kokkinakis took control with his increased aggression and weight of shot.

Still, the relentless Wawrinka took the fourth stanza to a tie-break, in which Kokkinakis had a shocker, dishing up five straight unforced errors.

But Kokkinakis reeled off the first four games in the decider and, even though the Swiss dug deep to earn a break-back, not even a dismal intervention from the umpire, giving the Aussie a time violation on the final match point, could derail him from setting up a third-round clash with 11th seed Karen Khachanov.

Earlier, Hunter had briefly upgraded from Storm to 'Hurricane' before her gale of winners subsided and her chance of her greatest win against the former world number three Svitolina was simply blown away.

"I'm definitely not deflated," said the proud Hunter, who had completely dominated her illustrious opponent early on behind a cracking forehand that produced 11 first-stanza winners.

Out on court 6, world number 69 Kubler, the last Aussie man standing at last year's Roland Garros, found 36-year-old Fognini, who's dropped to 130 in the rankings, to be on one of his focused days as the Italian gave him a bit of a clay-court lesson.

Aussies on day five at the French Open:

Men's singles, second round

18-Alex de Minaur v Tomas Martin Etcheverry (ARG), starting 7pm AEST

Max Purcell v 27-Yoshihito Nishioka (JPN), starting about 9pm AEST

AAP