The one-time Federer-slaying wunderkind of Australian tennis is now 30, doesn't know how the hell that happened, and concedes gravely: "My right arm isn't as functional as probably the average human…"
But guess what? The great survivor is back … and still believing.
At Roland Garros, where Kokkinakis has enjoyed so many of his fiercest duels, the popular Adelaide warrior will set out on Monday at the start of a 12-month odyssey which he accepts could be the last hurrah in a distinguished but luckless career.
Since pulling out of the Australian Open, after reinjuring the shoulder that had required ground-breaking surgery to save his career, he's had yet another rehab battle to return and, frankly, doesn't know how the latest comeback will turn out.
"I wasn't sure I'd even be able to step back on a tennis court and try and play at full capacity, so I've done well," he said having played his first couple of matches since January in Croatia earlier this month.
"The surgery I had was not normal. I'm giving myself a pat on the back that I've got back here. If my arm's positive, I'm positive, so we'll see. I don't know. I feel like I've kind of been through it all at this point.
"I always feel 'not again' after an injury, but it's 'not again' for a few days and then pick yourself up and go again. What other choice do I have? If I don't give it a crack, I would be regretting not giving it a go."
It's been hellish tough, though, for a man who this time last year had ditched his tennis for some TV commentary.
"There were many months where it wasn't normal," he says. "For a while, couldn't lift my arm over to the side, had to get my mate to floss my armpit after I had a shower to dry that off, because of the surgery.
"It's something that I've kind of gotten used to, it's my new normal."
His protected ranking could give him a chance to play the next four slams, starting with his date with Frenchman Terence Atmane in the opening round where he's perfectly happy for the madly partisan Roland Garros boo boys to get into him.
"That's the one thing I've always thought about in those dark rehab times, just the atmosphere and energy that you feel on court here," he said, recalling how he downed Stan Wawrinka in a "crazy" 2023 affair and how he had three five-set "absolute wars here" in 2024.
"These are things you can't replicate when you're done with tennis. So I owe it to myself at least to see how I go the next year and then I'll probably make a decision after the next 12 months to see how my arm goes, if I'm able to play further or not. I'm seeing what I've got left".
If Kokkinakis's heart has anything to do with it, we can safely say 'plenty'.
