The home player was given a time violation and then mocked Nadal's serve, by touching his hair on either side and then his shorts.

French opponent Gilles Simon also did his own impression of the Spaniard in a round-two match which Kyrgios, the 23rd seed, won 6-2, 6-4, 4-6, 7-5 at Melbourne Park.

Both Kyrgios and Nadal have exchanged words in the past, with the top seed accusing the Australian of "lacking respect" after he served underarm against him at the Mexico Open in February.

Kyrgios has described Nadal as "super salty".

The Spanish player also won his round two clash today, 6-3, 7-6, 6-1 against Argentina's Federico Delbonis.

He is hoping for a 20th grand slam title, which would move him level with Switzerland's Roger Federer, and a second in Australia after his 2009 triumph.

If both Kyrgios and Nadal win their third-round games, they will play each other in round four.

"I started my service motion, and there weren't any extra curricular activities I was doing before my serve to waste time," Kyrgios said.

"That's the ref's discretion if I went over the clock or not."

Elsewhere in the men's draw, Russia's fourth seed Daniil Medvedev beat Spanish qualifier Pedro Martínez 7-5, 6-1, 6-3.

Austria's fifth seed Dominic Thiem was given a huge scare by Australian wildcard Alex Bolt, before eventually winning in five, 6-2, 5-7, 6-7, 6-1, 6-2.

Alexander Zverev, Germany's seventh seed, defeated Egor Gerasimov of Belarus 7-6, 6-4, 7-5.

Swiss 15th seed Stan Wawrinka, who won the Australian Open in 2014, prevailed from a five-set duel with Italy's Andreas Seppi, winning 4-6, 7-5, 6-3, 3-6, 6-4.

In women's action, Czech second seed Karolína Plíšková brushed aside Germany's Laura Siegemund 6-3, 6-3, as she seeks a maiden grand slam title.

"I'm happy to get through as this was an ugly match for me," she said.

Romania's Wimbledon champion Simona Halep, seeded fourth, beat Britain's Harriet Dart 6-2, 6-4, and Ukrainian fifth seed Elina Svitolina accounted for American Lauren Davis 6-2, 7-6.

Swiss sixth seed Belinda Bencic knocked out Latvia's former French Open champion Jeļena Ostapenko, 7-5, 7-5.

Germany's 2016 champion Angelique Kerber, the 16th seed, saw off Australian wildcard Priscilla Hon 6-3, 6-2.

Third-round matches begin tomorrow.

Today's play on the outside courts was disrupted by rain depositing dust.