'Utter madness': Alex de Minaur stuns with 'insane' display against Rafael Nadal

He may not have won the match, but Alex de Minaur certainly won over the tennis world with his extraordinary display against World No.1 Rafael Nadal at the ATP Cup.

The man with the best motor in tennis added some power to his package but even that wasn't quite enough to get De Minaur over the finish line on Saturday night.

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De Minaur lost a thrilling 4-6 7-5 6-1 match to Nadal, as the Australians bounced out at the semi-final stage with Nick Kyrgios earlier delivering his poorest match of the tournament in going down to Roberto Bautista Agut.

Kyrgios's 6-1 6-4 defeat had left de Minaur needing an unlikely victory to push the match to a deciding doubles clash.

But adopting a similarly aggressive game plan to Belgium's David Goffin, who downed Nadal on Friday night, de Minaur was outstanding, hitting winner after winner to put the 19-time grand slam champion on the back foot.

"Obviously I knew the task at hand, and I knew that if I wanted to hurt Rafa I was going to have to play like that," de Minaur said.

Breaking Nadal on his first service game, he held firm to take the opening set and went toe-to-toe with the Spaniard for much of the second.

After a break-point chance at 5-5 to serve for the match, things then started to unravel for de Minaur.

Nadal snatched the set with his only opportunity as part of a run of six-consecutive games to effectively seal the match.

The irrepressible world No.18 pinched a break back but it wasn't enough as Nadal avoided losses in back-to-back matches for the first time since October 2016.

The tennis world was in awe of de Minaur’s remarkable display, especially when he shocked Nadal to win the first set.

“Rafael Nadal has spent his career in control of everything – control of where his water bottles are, control of the amount of time between points, control of the rallies,” American legend Jim Courier said in commentary for Channel Nine.

“He has spent a lifetime living off his forehand. He is getting far fewer forehands tonight than he almost ever gets and that is because de Minaur is taking it too him so much.

“Less than half of the rally shots tonight have come on the forehand wing. He (de Minaur) has taken Nadal’s weapon away from him so far. This is astounding.

“What this is so far is almost perfection from Alex de Minaur. He has given Nadal the business psychologically as well. He is right in his kitchen, rattling the pots and pans.”

Kyrgios comes undone

Earlier, the Kyrgios steam train was derailed by Bautista Agut.

A shadow of the player who had racked up a 3-0 singles record and a decisive doubles win at the teams tournament, Kyrgios struggled from the outset and never recovered.

Down 5-0 in the opener, the best the world No.29 could do was hold serve to ensure he could start up the second with ball in hand.

A tighter contest ensued early in the second but, when Kyrgios coughed up a break after an ill-advised trip to the net off a second serve, the match was as good as done.

Still, it has been a good Australian Open tune-up for Kyrgios, who had logged an impressive win against world No.6 Stefanos Tsitsipas and a heroic doubles win with de Minaur over Great Britain during the tournament.

Spain will play the Novak Djokovic-led Serbia in Sunday night's final after the Serbs beat Russia 3-0 in the other semi-final.