Nick Kyrgios: "I feel like I've made progress as a human"

In the end he fell just short, losing 6-3 3-6 7-6 (6) 7-6 (4) despite a home crowd cheering him to the rafters – something that certainly has not always happened.

Kyrgios said: "I'm shattered to have lost tonight. Obviously these are the matches that I want to win the most. But overall this summer has been fun.

"I feel like I've made progress as a human. A tennis player, I don't really care about as much. But I feel good. I want to keep going in this direction, for sure.

"The trouble for me is being able to actually just produce the same attitude over and over again. Hopefully I can keep doing it. I'm just taking it day by day, trying to be positive, just bring positive vibes."

The scoreline was the same as in their second-round clash at Wimbledon last summer but this time the tennis took centre stage.

The SW19 showdown had a real edge to it after some very public needle, with Nadal accusing Kyrgios of lacking respect following a feisty match in Acapulco and the Australian branding his opponent "super salty" in an interview on the No Challenges Remaining podcast.

Kyrgios said: "I felt a lot closer this time, especially in the 5-5 game in the third set, where I was at deuce a couple of times. He played some unbelievable points. I felt like, if I got that third set, I would have really, really been on top of him."

After a subdued start, the home star roused himself at the start of the second, saving a break point with the help of a tweener and then leaping and punching the air with delight when he broke the Nadal serve.

The third set was the peak of the contest, with Kyrgios doing all he could to flummox Nadal, mixing explosive ground strokes with slow balls, forehand slices, drop shots, an underarm serve and everything in between.

The tie-break saw Kyrgios smash a racket and miss a 135 miles per hour second serve at 5-5, only for Nadal also to double fault after a momentary disruption because of a crying baby.

But Kyrgios netted a forehand on the Spaniard's second set point and, although he broke Nadal when he served for the match at 5-4 in the fourth, the world number one prevailed in another tie-break.

John McEnroe was among Kyrgios' admirers, saying on Eurosport: "If Nick plays anything like he did tonight then he can be in the top 10 by the end of the year. I loved watching Nick play tonight. Let's hope and pray it continues."

Nadal and Kyrgios come from different ends of the tennis spectrum but the former insisted before the match that a fully-focused Kyrgios is good for the sport, and he reiterated that view.

"When he's playing like today, with this positive attitude, he gives a lot of positive things to our sport so I encourage him to keep working like this because he is one of highest talents that we have on our tour and I like the Nick Kyrgios during the whole of this tournament," said Nadal.

The top seed, who next faces Dominic Thiem, was generally happy with his display but branded the game he played to drop serve at 5-4 in the fourth set "scary".

"I am enough humble to accept that sometimes I am nervous and I can have mistakes," he said afterwards.

Thiem was hugely impressive in a 6-2 6-4 6-4 victory over Gael Monfils to reach the last eight here for the first time.

The other quarter-final in the top half of the draw will pit 2014 champion Stan Wawrinka against seventh seed Alexander Zverev.

Wawrinka is working his way back to the top of the game following knee surgery in 2017 and he claimed one of the best wins since then, beating fourth seed Daniil Medvedev 6-2 2-6 4-6 7-6 (2) 6-2.

The veteran Swiss said: "I think last time I played so well was before the surgery. I'm really happy again the way I'm fighting, the way I'm finding solutions and the level of the game."

Zverev arrived in Melbourne in poor form and with his serve apparently in crisis but is yet to drop a set, with his latest triumph a 6-4 6-4 6-4 success against Andrey Rublev, whose 15-match winning run came to an end.