Tennis great John Newcombe says Nick Kyrgios should be pulling out all stops to beat fellow Australian Jordan Thompson and set up a Wimbledon blockbuster with Rafael Nadal.

Newcombe, though, can’t be certain Kyrgios actually will, admitting he has no idea what to expect from the enigmatic Australian who hasn’t reached a grand slam quarter-final in four-and-a-half years.

Victory over Thompson on Tuesday would set up a spicy showdown with Nadal on Thursday, unless the 18-time French Open champion came unstuck in his opener against Japanese world No.258 Yuichi Sugita.

Kyrgios versus Nadal is the showstopper that, apart from Thompson camp, the entire tennis watching world yearns.

The two have traded barbs all year, with Kyrgios branding Nadal “super salty” and the Spaniard accusing the Canberran of lacking respect.

But asked where Kyrgios’s tennis and head were entering his sixth Wimbledon tilt, Newcombe said: “About where his ranking is”.

“You don’t know. You wouldn’t know what was going to happen, so it’s anybody’s guess.

“I would imagine that he would see that draw and he would bust his guts to beat Jordan because he fancies himself against Rafa, especially on grass.

“He seems to play his best tennis when he’s got nothing to lose.

“It could be an interesting match after all the talk.”

Unseeded at the All England Club for the first time since 2014, when he upstaged Nadal as a 19-year-old on debut, Kyrgios is at a career crossroads, according to Newcombe.

“He’s been at one for a few years,” said the former world No.1 and triple Wimbledon champion.

“He got his ranking to 13 a couple of years ago and now he’s 43. I mean, that sort of speaks for itself.

“He’s 24. He should be reaching his peak.”

Thompson is certainly reaching his peak.

After charging to the final in ‘s-Hertogenbosch and then the semi-finals this week in Turkey, the 25-year-old sits just one spot below Kyrgios at a career-high No.44 in the world.

But Thompson knows he’ll need to sustain his stellar grass-court form to deny Kyrgios a grudge match with Nadal.

“I don’t want to let him get past me, but I’ve got a job on my hands,” he said.

“He’s got an incredible serve. It’s very unreadable and I’ve got to do everything in my power to try and just get it back into play.

“Then I’ve got to look after my own serve so it’s going to be a big task.”