Ashleigh Barty has finally been afforded top billing at Wimbledon – and on one of the biggest days of the championships.

After having to play second and third fiddle in her opening two matches, Barty will grace tennis’s most famous Centre Court as world No.1 for the first time on Saturday.

Australia’s new superstar will be playing before some of the UK’s highest-profile celebrities when she takes on British wildcard Harriet Dart.

Middle Saturday at the All England Club traditionally celebrates the country’s greatest athletes, with the likes of David Beckham and wife Victoria, Olympians and cricket and football champions, regulars in the Royal Box.

Club officials don’t release the identities of the Royal Box guests until the day, but last year Sir Bobby Charlton joined Australian legend Rod Laver in the Royal Box.

Laver will again be front and centre as Barty opens proceedings before tennis royals Rafael Nadal and Roger Federer play their men’s third-round matches on Centre Court.

Laver will be feted on the same court where he won four singles titles, the last in 1969 – the year of his second grand slam sweep. He will be presented with a replica trophy to mark the 50th anniversary of the ’69 triumph.

Barty, who hasn’t dropped a set in nine matches since the French Open semi-finals, is refusing to take her 182nd-ranked opponent lightly as she looks to enter Wimbledon’s second week for the first time.

“There’s an element of danger against everyone you play,” Barty said.

“You have to make sure you know exactly how you want to play the match.

“I haven’t played with her before, haven’t hit with her. Obviously a little bit new for both of us.

“I’ll make sure that we’re prepared as best we can, we have a game plan, try to go out there and execute.”

Shunted to Court 2 for her second-round match after launching her title quest on Court 1, Barty will be appearing on Centre Court for the first time since she was 17 and partnering fellow Australian Casey Dellacqua in the 2014 women’s doubles final.

A fan favourite wherever she plays, the top seed isn’t concerned about facing one of Britain’s last hopes in front of her home crowd.

“I wouldn’t be playing a British crowd; I’m playing against Harriet,” Barty said.

“Yes, she’ll get more support being in Britain, as I would if we were in Australia. It’s no different.”

Victory for Barty would put her into a last-16 clash with either Swiss 13th seed Belinda Bencic or American Alison Riske on Monday.

“I mean, I don’t need to worry about that for at least another couple of games if she closes it out. We’ll worry about it then.”

John Millman, the last Australian survivor in the men’s draw, plays American Sam Querrey in the third round in the first match on Court 12.

Blockbuster rescheduled

Serena Williams and Andy Murray’s mixed doubles first-round match at Wimbledon was cancelled evening by organisers, who rescheduled it to be played on Saturday.

The two tennis stars had teamed up on Wednesday to play in the event.

Former Wimbledon singles champion Andy Murray and legend of the game Serena Williams leave the court after a practice session. Photo: Getty

Serena is still competing in the singles, while Murray hasn’t played singles since the start of the year because of injury, but appears to be making a tentative comeback through doubles.

The celebrity pair had been due to play Andreas Mies and Alexa Guarachi on Centre Court, but moments after the preceding match went to a third set at around 7:15pm local time on Friday, organisers announced the mixed doubles clash was being cancelled.

It was later rescheduled for Saturday on a court, and at a time, “to be arranged”.

Australian singles matches at Wimbledon on Saturday:

Ashleigh Barty v Harriet Dart (GBR), 10pm AEST

John Millman v Sam Querrey (USA), 8pm AEST

Latest women’s results:

S. Halep def. V. Azarenka 6-3, 6-1

S. Zhang def. C. Wozniacki 6-4, 6-2

E Svitolina def. M. Sakkari 6-3, 6-7 (1-7), 6-2

C Gauff def. P. Hercog 6-3, 6-7 (7-9), 5-7

KA Pliskova def. SW Hsieh 6-2, 2-6, 6-4

K Muchova def. A Kontaveit 7-6 (9-7), 6-3

D Yastremska def. V Golubic 7-5, 6-3

P Martic def. D Collins 6-4, 3-6, 6-4

Latest men’s results:

F Verdasco def. T Fabbiano 6-4, 7-6 (7-1), 6-4

G Pella def. K Anderson 6-4, 6-3, 7-6 (7-4)

N Djokovic def. H Herkacz 7-5, 6-7 (5-7), 6-1, 6-4

R Bautista Agut def. K Khachanov 6-3, 7-6 (7-3), 6-1

D Goffin def. D Medvedev 4-6, 6-2, 3-6, 6-3, 7-5

M Raonic def. R Opelka 7-6 (7-1), 6-2, 6-1

B Paire def. J Vesely 5-7, 7-6 (7-5), 6-3, 7-6 (7-2)