Alex De Minaur has clawed his way past evergreen Frenchman Adrian Mannarino to join countryman Alexei Popyrin in the Australian Open third round.

The only seeded home hope in the tournament after the injury-forced withdrawal of Nick Kyrgios, De Minaur prevailed 7-6(3), 4-6, 6-4, 6-1 in a battle lasting three hours and 29 minutes on Thursday night.

After going down a break in the fifth game of the match, the 23-year-old was able to rebound and break Mannarino straight back on John Cain Arena.

It proved a turning point with the 22nd seed then using the momentum to storm ahead to lead two sets to one.

It took the wind out of the 34-year-old's Mannarino's sails with his frustration growing alongside his unforced error count.

A buoyant De Minaur took full advantage, playing almost flawless tennis as he broke his opponent and then consolidated for a commanding 4-1 lead.

Another break gave the Aussie a chance to serve out the match, which he did without dropping a point.

He said he had to "dig deep" to overcome the dogged left-hander.

"It was a battle and I found a level I didn't know I had," De Minaur said.

"I was on cloud nine for a whole set and a half and that's down to you (the crowd) so let's keep it going."

De Minaur said he was inspired by the performance of Popyrin, who earlier shocked fifth seed Taylor Fritz on the same court.

"We've grown up together and he played a hell of a match," De Minaur said.

"He inspired me and I was glad I was able to pull through."

He faces another French player in the third round after Benjamin Bonzi upset Spaniard Pablo Carreno Busta in five sets, winning the match in a championship tiebreak.

De Minaur's best result thus far at the Open came last year when he reached the fourth round.

He arrived at Melbourne Park this year with rocketing confidence after claiming the scalp of top seed Rafael Nadal at the season-opening United Cup and taking down two-time Open runner-up Daniil Medvedev at the Paris Masters in November.