HOMEGROWN tennis champion Casey Dellacqua has tipped Australia as a “roughy” to take out the 2019 Hopman Cup.

The former Australian number one who started her career at the Kingsley Tennis Club said Ash Barty and Matt Ebden had been playing great tennis.

However, she said it would be hard to go past team Switzerland – Roger Federer and Belinda Bencic – who would be defending their 2018 title.

“Germany will be keen to lift that trophy too,” Dellacqua said.

Tournament director Paul Kilderry has tipped Germany – Angelique Kerber and Alexander Zverev – as the ones to beat.

Mr Kilderry announced at the Hopman Cup 2019 launch this morning that children would get free entry for day sessions.

“We want to get as many kids and families watching and then hopefully they’ll pick up a racket and take part in the game,” he said.

Former world number one Serena Williams is returning to Perth for the Hopman Cup and will play against Federer for the first time.

Williams (37) played the Hopman Cup in 2015 and 2016 before beginning her season in Auckland last year.

But the 23-time Grand Slam singles tournament winner was announced as a major drawcard for the event at RAC Arena this morning.

It will be the fifth time Williams, who gave birth to her daughter Alexis on September 1 last year, has played at the Hopman Cup.

The American will play alongside Frances Tiafoe.

America has been drawn in the same pool as Switzerland, meaning Williams is likely to face off with Swiss star Federer in the mixed doubles on January 1.

Mr Kilderry said Williams had been keen to return to the 31st Hopman Cup from early in the year.

Tourism Minister Paul Papalia said the match up between Williams and Federer could be a once in a lifetime opportunity.

“We have the best female player of all time playing the best male player of all time and they’ve never played each other before,” Mr Papalia said.