The ill-starred 30-year-old was forced to pull out at the start of the third set of his second-round contest with Spanish veteran Pablo Carreno Busta on Wednesday with a recurrence of the chronic right shoulder problem that's been placing a question mark over his career.
But the defiant 30-year-old, who said he'd pulled out because he feared the match might finish his season, was adamant: "I'm doing some scans tomorrow, I'm trying to be optimistic."
Kokkinakis had cut a forlorn figure after duelling with typical bravery to level at one-set all 5-7 6-4 after two hours in the 32C heat at Roland Garros, but having clearly been in some discomfort throughout, as he constantly tried to shake shake out his serving shoulder, he needed physio treatment after the set.
He conversed at length with his team during that break but hauled himself up to start the third set, only to lose the first game to 30.
Before his own service game, he evidently realised there was no way he could continue, hitting the balls away and walking to the net, where the 34-year-old Carreno Busta offered him sympathy.
"Yeah, just struggling with the same injury," Kokkinakis reported afterwards. "I could feel it getting worse. I kind of came into the match with a lot of doubts, because I wanted to go out there and give it a crack, but I knew it didn't feel right. It progressively got worse with the match."
But asked if he'd be flying home, he said: "Not yet, not yet. If I'd kept playing, that's me probably out of Wimbledon and maybe even US Open, and something bad to happen. I'm trying to be optimistic, I just want it play the slams one more time. That's my goal."
It was a wretched setback for the Adelaide warrior who had written another remarkable chapter in his long injury fight by battling back in another exhausting five-setter -- the 16th of his career -- on Monday to beat Frenchman Terence Atmane and silence a baying home crowd.
But he had feared, rightly, that the recovery after a draining four-and-a-quarter hour slog in the sun would be challenging, and ultimately it proved too much for a man who's only managed to complete four matches since a ground-breaking pectoral surgery in February 2025 involved attaching a dead man's Achilles to his shoulder.
He said on the eve of the tournament that he planned to give himself 12 months, and play in the four grand slams, to see whether it would be possible to extend his career.
Carreno Busta was hugely sympathetic. "I'm so sorry, because he's a great guy, a great opponent, and I hope he can recover 100 per cent in the future.
"I know that injury is probably the worst thing a tennis player or a sportsman can have, but I know he's a fighter and I hope he can recover as soon as possible."
On Australia's first winless day of the tournament, Sydneysider James Duckworth, the country's new No.2 in the live rankings, put up an excellent scrap against Spanish teenage star Rafael Jodar, only to succumb 6-1 6-7 (5-7) 6-4 7-5 to the 27th seed.
But the 34-year-old Duckworth put up a much better showing against the new "Rafa'' than No.1 Alex de Minaur did when he got trounced by the 19-year-old in Madrid.
The soaring youngster, who took a heavy tumble into the dirt when losing the second-set tiebreak and later needed a medical timeout for a thigh problem that he perhaps incurred in the fall, still showed real steel as he prevailed in three hours 22 minutes.
