Rafael Nadal faces a tricky test in his quest for a men’s record 21st grand slam title when he takes on Denis Shapovalov in the Australian Open quarter finals on Tuesday, but the Spaniard is relishing another battle with his fellow left-hander.

Nadal returned to action on the ATP Tour for the first time since August 5 earlier this month and has slowly moved into top gear at the first major of the year, reaching the last eight after a gritty performance against Frenchman Adrian Mannarino.

The sixth seed expects another challenging encounter against Canadian Shapovalov, who beat him as a teenager in their first meeting on the hard courts at Montreal in 2017, although the 35-year-old has since improved the head-to-head record to 3-1.

“After that match I said he’s going to be a potential multi-grand slam winner,” Nadal said of the 22-year-old. “And I still think that if he’s able to keep improving, he will be a multi-grand slam winner.

“He has a lot of amazing things in his game, and his results say that. When he’s playing well, it’s very difficult to stop him.

“It’s going to be a tough one for me ... It’s a match to try my best, to play at my highest level if I want to have chances to go through,” Nadal told reporters.

“Yeah, I’m excited about it. I didn’t expect to be where I am weeks ago.”

“I’m definitely expecting a long battle out there,” Shapovalov said of facing Nadal.

“Obviously, he makes you play a lot. His defence is very good. He’s very good at what he does.”

World No. 1 Ashleigh Barty steps up her bid to emulate Chris O’Neil and give Australia a first home women’s singles champion at Melbourne Park since 1978. Standing in her way is American 21st seed Jessica Pegula, who has never reached the semi-finals.

Resurgent American Madison Keys, a former US Open runner-up, meets Czech fourth seed and French Open champion Barbora Krejcikova in an intriguing contest.