NICK KYRGIOS does not need to change, according to Australia Davis Cup captain Lleyton Hewitt.

The volatile 21-year-old takes on Andy Murray on Centre Court on Monday for a place in the quarter-finals of Wimbledon.

Kyrgios is undoubtedly a threat to the top players but the negative side of his personality has also been on show regularly at the All England Club with rants at umpires and his support box.

READ MORE: Kyrgios: I've got the tools to knock Murray out on his own backyard

Hewitt, speaking to Press Association Sport of behalf of HSBC, said: "His ranking's on the right path for sure and he's still only 21 years old.

"He's got a big game, a lot of fire power and can match it with the best players in the world, and we've seen that before.

"He's got to keep his passion, that's the biggest thing. When he is up and about, he's playing his best tennis. You don't want to take that flair and flashiness away from him. That's the thing that can make him a top-10 player.

"Everyone loves different personalities. People want to come to the tennis to watch a guy like Nick play."

The tournament has a different dynamic now following the shock exit of two-time defending champion Novak Djokovic, leaving Murray as the title favourite.

READ MORE: Kyrgios: I've got the tools to knock Murray out on his own backyard

Kyrgios said: "I think as soon as Novak loses, you look at Andy and you look at Federer's eyes light up. They think that their chances probably doubled. I think a lot of people in the locker room now believe they can win it."

The Australian counts himself among the title hopefuls but his record against his good friend Murray does not offer too much hope.

Bizarrely, Monday's match will mean Murray and Kyrgios have played each other at all four slams in the last 18 months.

The Scot has won the previous three, with his only lost set coming at the US Open last summer, but Kyrgios did manage a win over his rival at the Hopman Cup in January.

"I thought I made some inroads (at the US Open)," said the Australian.

"Finally won a set against him in a grand slam. I feel like I know what to do but it's hard to actually go out there and execute against such a player like him.

"I definitely feel like he's beatable. He's only human. This is probably my best surface, my best chance to beat him.

"I rarely walk into a tournament and don't think I can win it."

Murray has been in fine form in his three matches so far, beating Liam Broady, Lu Yen-hsun and John Millman.

But Kyrgios is undoubtedly a significant step up and a player who can boast five wins over top-10 players already this season.

"He is improving all of the time," said Murray. "He likes the big courts, the big matches. He has performed well in those situations before."

READ MORE: Kyrgios: I've got the tools to knock Murray out on his own backyard

Monday sees all fourth-round singles matches on the schedule, and Centre Court fans will be treated to a bumper programme also featuring Roger Federer and Serena Williams.