After de Minaur had delivered a consummate 7-5 6-1 6-4 win over Jaume Munar on Thursday to make the last 32 at Roland Garros for the first time, Kokkinakis stole the Aussie show by coming from two sets down to beat Italian qualifier Giulio Zeppieri 1-6 4-6 6-3 7-6 (7-5) 6-2.
After fighting back from two sets to one down to beat Alexei Popyrin in an all-Australian five-set classic which concluded at 11.37pm on Tuesday, the Adelaide marathon man sealed his triumph under lights again at 11.35pm in front of boisterous fans on Court 10.
Alex de Minaur celebrates after his terrific win over Jaume Munar. (EPA PHOTO)
"I'm running on fumes at the moment, it's tough. I really need to do it easier but guys are good and I struggle with my focus a lot of the time," said Kokkinakis, next faces American No.1 Taylor Fritz.
"Finding a win ugly is better than not winning at all, but it definitely catches up with you in these grand-slam matches."
The three-hour 45 minute grind, interrupted by a rain break for an hour, was the third time Kokkinakis has made the third round at Roland Garros, and his fourth successive victory in a five set-match after the heartbreak of his epic 4.05am loss to Andy Murray in Melbourne last year.
It was an astonishing effort after Zeppieri had served for the match in the fourth set at 5-3 only for the 28-year-old Australian to simply refuse to bend.
Late in the fourth set, as tensions rose on and off the court, Kokkinakis had some choice words for an Italian fan he felt was hissing at him between serves.
He also scolded Zeppieri for shouting 'c'mon' after winning a point with a lucky smash off the frame.
But at the end of another rain-hit day in Paris - it's not for nothing this year's event is being nicknamed the 'Drench Open' - it was a delight for Kokkinakis to see two Australians battling through.
"It's good. Alex is leading the way for us as always and I'm trying to follow in his footsteps and play as well as I can," said Kokkinakis.
De Minaur made light of more Paris rain trying to dampen his title assault, powering past old Spanish clay-court pal Munar to reach the last 32 for the first time in eight attempts.
There he will meet German big-hitter Jan-Lennard Struff.
The Australian No.1 didn't let the hour's rain break affect him as he quickly resumed where he left off, eclipsing the hardened clay-courter with an assured, attacking display.
Munar became distinctly irritable, living up to his nickname of 'Jimbo' as a kind of Spanish answer to volatile US great Jimmy Connors.
But while Munar argued with the umpire and got the supervisor called to court to adjudicate over a complaint, de Minaur kept his head down, refused to be distracted and went on to carve out his impressive two-hour 11 minute win.
"It feels great," he said of getting past the second round at last.
"It's something that I've always thought that I was going to be able to achieve in my career.
"Just good to finally be able to be in the third round and keep on going, because ultimately my goal is not to make the third round, it's to go for bigger and better things.
"And I'm just keeping myself alive and ready for the next round."
