MELBOURNE - It was a chaotic opening day of first round matches at the Australian Open in Melbourne on Monday, with a number of shock exits and more than enough drama for the 72,000 spectators in attendance.

In the men's bracket, top seeds Rafael Nadal, Grigor Dimitrov, Pablo Carreno Busta and Jo-Wilfried Tsonga booked their places in the second round of the tournament, after breezing through their lesser known opponents with ease.

While local favorite Nick Kyrgios also impressed with a stellar straight-set victory against Brazilian Rogerio Dutra da Silva.

However not everything went to plan for some of the big names.

World number 9 Jack Sock was forced out by Japan's Yuichi Sugita in 4 sets, while last year's US Open finalist Kevin Anderson lost a 5-set thriller to England's Kyle Edmund.

In another big surprise, Aussie Matthew Ebden overcame 16th seed John Isner in a four-set battle that delighted Melbourne fans.

But the biggest shock of day one came when 20-year-old Swiss hitter Belinda Bencic dispatched last year's Australian Open finalist Venus Williams in straight sets, making it the first time since 1997 neither Williams sisters would make an appearance in the second round of the tournament.

The disappointed 7-time Grand Slam winner told Xinhua after the match, Bencic played "above and beyond."

"I don't think I played a bad match," Williams said, "Maybe I had a few too many unforced errors. I think she just played well."

Another high profile exit came when China's Zhang Shuai fought back from a set down to defeat 2017 US open winner Sloane Stephens.

But the drama wasn't finished there as another American superstar crashed out of the tournament, when Timea Babos from Hungary finished CoCo Vandeweghe in straight sets.

The match featured a truly bizarre moment when Vandeweghe was issued a time violation after the fiery competitor waited "too long" for courtside banana snack at the end of the first set.

Former world number one Sam Stosur also failed to make her way out of the first round.

However Caroline Wozniacki, Elina Svitolina, Jelena Ostapenko and Julia Gorges all made light work of their opening matches and China's Duan Yingying blasted her way past Colombian Mariana Duque Marino in straight sets 6-0, 6-1.