Alex de Minaur has left commentators and fans in shock with a barely-believable moment.
The second seed required just 55 minutes to record a 4-1 4-1 4-2 victory over an opponent ranked almost 600 places below him.
But despite the mismatch, Caruana still managed to push De Minaur to the extreme, highlighted by an incredible moment in the first set.
De Minaur retrieved a ball at the far extreme of his forehand side, before racing across court to do the same on the backhand side.
He was then forced to sprint to the net and produced another remarkable get, before forcing Caruana into a weak lob that he easily put away.
The Aussie had no right to win the point, but showed all the fighting qualities that have led to comparisons to mentor Lleyton Hewitt.
“That is incredible,” a TV commentator said.
SEND. NEW. SHOES… 👿
— Tennis TV (@TennisTV) November 6, 2018
Fans also couldn’t believe De Minaur’s insane speed.
In presser yesterday De Minaur was asked to name his biggest strength. He said his speed, "because basically all I'm doing right now is running from left to right". Joked with Fritz that he'd switch with him, get a bit taller & give Fritz some of his speedhttps://t.co/7uhTRqzFC5
— Reem Abulleil (@ReemAbulleil) November 6, 2018
The World No.31 now has 25 tour-level wins in 2018, after he started the year with just two and a ranking of 208th.
“I’ve had a great year and I’m enjoying every second of it. I couldn’t think of a better start today,” the 19-year-old said in his on-court interview.
De Minaur saved both break points he faced against Caruana and won 51 per cent of return points in the win that put him top of Group B.
“The main thing was to be very intense. With this format every single point counts…,” he said.
“You have to try and take care of your service games and not get into those awkward sudden-death deuces that can only get you into trouble.
“Play aggressive and have some fun here.”
De Minaur will face Andrey Rublev on Wednesday (local time) with a win over the Russian in three or four sets enough to guarantee a spot in the semi-finals for the only teenager in the eight-man round-robin event.