World number one Ashleigh Barty has sailed into the second round of Wimbledon with a dominant victory over China's Zheng Saisai.

Key points: Barty entered Wimbledon as the number one seed

Barty entered Wimbledon as the number one seed The 23-year-old will now face Belgian Alison Van Uytvanck in the second round

The 23-year-old will now face Belgian Alison Van Uytvanck in the second round Aussie men Kyrgios, Millman all progressed as well

The French Open champion needed just over an hour to dispose of the unseeded 25-year-old 6-4, 6-2 on Court One.

Barty was joined in the second round by fellow Australians Alex de Minaur, Nick Kyrgios and US Open quarter-finalist John Millman, who all safely progressed on an action-packed day two of the championships.

Barty said she and her team were taking their trademark relaxed attitude into Wimbledon, a tournament she won as a 15-year-old junior.

"We kind of came into it thinking 'hakuna matata', just try [to] relax and go for it," she said.

"[It] was really nice to come in here and get stuck into that first match."

Barty said she was "fangirling" on Court One, having played there as a junior.

"It was really nice, and [it was] just a beautiful court to start on," she said.

Barty had an impressive 90 per cent win ratio on her first serve in the match. ( AP: Kirsty Wigglesworth )

Barty raced to a 3-0 lead in the first set only for Zheng to fight back and level things up at 3-3 thanks to a series of unforced errors from the Australian.

However, the new world number one composed herself to take the opener.

The second set was more of a formality, with Barty cruising through after an early break of Zheng's serve.

The 23-year-old will now face Belgian Alison Van Uytvanck in the second round on Thursday.

The Australian will face world number 58 Alison Van Uytvanck on Thursday. ( AP: Kirsty Wigglesworth )

Former Australian tennis star, now coach and commentator, Louise Pleming, said there was a Barty buzz around the All England Tennis Club this year.

"It's fantastic walking around coffee shops and bars here. Everyone's talking about Australians, particularly Ashleigh Barty," she said.

Pleming said the key to Barty's success had been her rigorous preparation and her tight-knit team who kept her calm.

"She's really going to have to harness her time away from the court … when they're away from the court, they laugh and have a lot of fun and Ash really needs that," she said.

"Really taking care of that energy, that's the most important thing for Ash."

De Minaur, Kyrgios and Millman all progress, Tomic labelled 'embarrassing'

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 42 seconds 42 s Kyrgios through to the second round, while Tomic crashed out in 58 minutes

De Minaur also marched into the second round without dropping a set, the 25th seed swatting aside 2018 French Open semi-finalist Marco Cecchinato 6-0, 6-4, 7-6 (7-5) in a rematch of their tournament opener last year.

Next up for de Minaur is American world number 71 Steve Johnson, who took out Albert Ramos-Vinolas 6-4, 6-2, 6-3.

Kyrgios set up a Centre Court blockbuster with Rafael Nadal after denying his former junior doubles partner Jordan Thompson 7-6 (7-4), 3-6, 7-6 (12-10), 0-6, 6-1 in an epic all-Australian first-round encounter.

Nick Kyrgios overcame fellow Aussie Jordan Thompson. ( Reuters: Hannah McKay )

Five years after becoming the lowest-ranked player to beat a world number one at a grand slam since 1992, Kyrgios will reprise his Wimbledon rivalry with Nadal on Thursday after the Spaniard dispatched Japanese qualifier Yuichi Sugita 6-3, 6-1, 6-3.

"I can't wait. As soon as the draw came out, I was super happy that I saw him in my section," Kyrgios said.

Millman hammered Bolivian Hugo Dellien 6-2, 6-3, 6-4 and plays either Argentine Guido Andreozzi or Serb Laslo Djere next.

But Bernard Tomic, Matt Eben, Samantha Stosur and Arina Rodionova all followed Thompson out the exit gates.

Tomic lost 6-1, 6-2, 6-4 to dual semi-finalist Jo-Wilfried Tsonga, while Ebden lost 6-4, 3-6, 6-3, 6-2 to 24th seed Diego Schwartzman.

Social media channels lit up with Wimbledon followers slating Tomic's apparent lack of effort with "appalling", "embarrassing" and "playing in slow motion".

Commentating on BBC TV, former British number one John Lloyd said he could have watched a more competitive match in his local park.

"Yeah, I mean, I played pretty bad," Tomic said.

"I just played terrible."

But when asked if he'd given his best effort, Tomic rolled his eyes and said, "next question, please".

Stosur succumbed 6-2, 7-5 to Spanish veteran Carla Suarez Navarro and Rodionova's run from qualifying ended in a 6-2, 6-3 loss to Taylor Townsend.

ABC/AAP