Serena Williams has said she did not know Ashleigh Barty was world number one until being told at her pre-Wimbledon press conference on Saturday.

Williams, though, did say she was happy for Barty and was gushing in her appraisal of the Queenslander's game.

"Wow, that's great," the 23-times grand slam champion said.

"I think Ash, I don't know anyone that has anything negative to say about her. She's like the sweetest, cutest girl on tour. She's so nice.

"She has the most beautiful game, such classic shots. I mean, she does everything right. Her technique is, like, flawless.

"Obviously I'm happy for her. Yeah, it's good. It's good for her."

Aussies' Wimbledon first-round matches Women's singles: 1 Ashleigh Barty v Zheng Saisai (CHN)

1 Ashleigh Barty v Zheng Saisai (CHN) Ajla Tomljanovic v 29 Daria Kasatkina (RUS)

Ajla Tomljanovic v 29 Daria Kasatkina (RUS) Daria Gavrilova v 8 Elina Svitolina (UKR)

Daria Gavrilova v 8 Elina Svitolina (UKR) Astra Sharma v 27 Sofia Kenin (USA)

Astra Sharma v 27 Sofia Kenin (USA) Samantha Stosur v 30 Carla Suarez Navarro (ESP) Men's singles: 25 Alex de Minaur v Marco Cecchinato (ITA)

25 Alex de Minaur v Marco Cecchinato (ITA) Nick Kyrgios v Jordan Thompson

Nick Kyrgios v Jordan Thompson John Millman v Hugo Dellian (BOL)

John Millman v Hugo Dellian (BOL) Matt Ebden v 24 Diego Schwartzman (ARG)

Matt Ebden v 24 Diego Schwartzman (ARG) Alexei Popyrin v Pablo Carreno Busta (ESP)

Alexei Popyrin v Pablo Carreno Busta (ESP) Bernard Tomic v Jo-Wilfried Tsonga (ESP)

The American superstar endorsed Barty as a genuine chance of becoming Australia's first Wimbledon singles champion since Lleyton Hewitt in 2002.

"She has a great game. I think she's really even-tempered," Williams said.

"She's just really chill. I feel like she's just so relaxed in a way. She's had a solid year, as well. It's not just the French Open. I believe she won Miami. She's had a really good year.

"Yeah, I think anything is possible."

Barty acknowledged it was a "new feeling" entering the All England Club as top seed.

"Something that I've never experienced before," she said.

"It hasn't really changed much, to be honest. We're still trying to go about all of our business, all of our preparations the same way.

Barty recently rose to world number one by winning the Birmingham tournament. ( Reuters: Carl Recine )

"We know what we've been doing has been working. For us, it's about trying to keep that normality as much as possible.

"There's more attention, there's more of that outside noise. But from what we're trying to do on the court, it hasn't changed much. We'll just keep trying to grow and be better every single day."

Barty and Williams could clash in the quarter-finals, but Williams isn't looking that far ahead, let alone at the prospect of matching Margaret Court's all-time record of 24 singles majors.

"I can't go into grand slams thinking about records," said the seven-times champion and last year's runner-up to Angelique Kerber.

Barty will launch her title assault against world number 43 Zheng Saisai, with former champion and one-time world number one Garbine Muguruza looming as a major obstacle in round three.

'Super salty' Nadal looms for Kyrgios, or Thompson

Nick Kyrgios won't have it easy at Wimbledon, facing Jordan Thompson in the opening round, with the winner likely to take on Rafael Nadal in round two. ( AP: Rebecca Blackwell )

Meanwhile, Nick Kyrgios's potential second-round showdown with Rafael Nadal is the talk of Wimbledon, with the possible grudge match dominating discussion after Friday's draw in London.

Kyrgios will open against in-form compatriot Jordan Thompson, with the reward for the victor being a likely confrontation with 18-time grand slam champion Nadal.

Unseeded for the first time since his stunning win over Nadal as a teenager five years ago, Kyrgios two months ago branded Nadal "super salty" in an extraordinary attack on some of tennis's biggest names.

Kyrgios also dubbed Nadal's uncle Toni "an idiot", having already infuriated Nadal while serving under-arm against the Spaniard in March en route to the title in Acapulco.

Kyrgios was highly critical of Rafa, and his uncle. ( AP: Rebecca Blackwell )

Fresh off his 12th French Open triumph this month, Nadal needs no added motivation to put Kyrgios back in his box, having hit out at Wimbledon officials this week over his seedings demotion.

The world number two was controversially relegated to third seed behind eight-time champion and world number three Roger Federer.

The two grand slam giants could square off in the semi-finals.

First, though, Nadal must get past Yuichi Sugita, and then Kyrgios or Thompson.

While Kyrgios will be favoured to win his opener, the former quarter-finalist has won only one match this grass-court season.

Thompson, six from seven and into this week's Antalya semi-finals in Turkey, will be anything but a pushover.

Gavrilova has the toughest assignment against eighth seed Elina Svitolina. ( AAP: Julian Smith )

Alex de Minaur, Australia's only seed in the men's event, will open his campaign against Italy's Marco Cecchinato.

Barty might be riding a 12-match winning streak, but as with most of Australia's six-strong women's contingent the draw offered her no favours, landing her in a loaded top quarter.

Qualifier Arina Rodionova, playing American Taylor Townsend, was the only Aussie woman apart from Barty not to draw a seed in the first round.

Daria Gavrilova has the toughest assignment against eighth seed Elina Svitolina.

Ajla Tomljanovic plays 29th seed Daria Kasatkina, Astra Sharma is up against 27th seed Sofia Kenin and Samantha Stosur tackles 30th seed Carla Suarez Navarro.

AAP