They've been side by side in the tennis world for nearly two decades, but when it comes to love, Venus Williams says her sister Serena is smarter than she is.

"She's a wise woman, she's actually getting a real life, she's paving the way once again for me. Maybe I'll grow up. It's been an awesome year for her," Williams said at her post-match press conference.

Serena Williams announced her engagement to Reddit co-founder Alexis Ohanian shortly before she touched down in New Zealand for the southern hemisphere tennis season.

Sisterly support ... Venus Williams. Photo: Getty Images

Venus said she didn't feel she had held back from personal happiness because of her tennis.

"You can't plan these things; you have to just live and see what happens."

Venus was last said to be dating model Elio Pis, who starred in the campaign for her Eleven fashion label, although she is notoriously private about her personal life.

Given the sisters have often shared a home, time will tell whether the engagement will prompt one of them to find new digs.

"It's up to them. They don't need any pressure from me ... they have to figure out this life together, that's their job. I just go with the flow," Venus said.

A-Tomic pink

Fashions at the Open are always a talking point and the first player to set tongues wagging was none other than Australian Bernard Tomic, whose orange striped warm-up kit caught the attention of several observers on day one.

Once he was on court it was the battle of the fluorescent warriors as Tomic, in neon watermelon shoes, took on Brazilian Thomaz Bellucci, whose yellow kit was a nice nod to his country's flag.

Bernard Tomic served up some bright fashion on day one of the Australian Open. Photo: Getty Images

Still on fashion, Spain's Garbine Muguruza said she loves to get out of her tennis gear and dress up in designer clothes.

Wardrobe change ... Garbine Muguruza shows her style both on and off the court.. Photo: Getty Images

"Once I get out of the court, I am changing completely. I love to wear high heels – I am obsessed. I have heels in all of the colours," said the 183-centimetre-tall seventh seed.

Tomic's fluoro Nikes were the talk of the fashion watchers on the opening day of competition. Photo: Getty Images

Wooing The Boss

In the lead-up to the Australian Open, organisers and sponsors send out invitation lists to any celebrity thought to be in town. It's like throwing chips at a flock of seagulls, in the hope at least a few big names will show.

Emirates, one of the key sponsors, is hoping to nail a big fish in Bruce Springsteen, who starts performing a string of shows in Australia later this month. Although his first Melbourne show isn't until February 2 – days after the Open champions are crowned, Emirates representatives have been talking to Springsteen's manager to try to lure the rock legend to a session.

Emirates is hoping Bruce Springsteen will find time in his touring schedule to catch some tennis. Photo: Getty Images

Other celebrities said to be invited – but not yet confirmed – include Nicole Kidman and Keith Urban, and Usain Bolt, who is due back after his Oaks Day appearance for the Nitro Athletics series. The event kicks off on February 4, but given how much Bolt loves to party, it wouldn't be surprising if he jets in early.

Due in town in February ... Usain Bolt may arrive early for the tennis, and to party. Photo: Getty Images

Stars to look out for on day two

Olympic swimmer sisters Bronte and Cate Campbell, newlyweds Carlton skipper Marc Murphy and Jessie Murphy, and Dale Thomas and Hayley Robertson will all be in attendance.

Other celebrities you may spot on Tuesday include comedian Tommy Little, actor Scott McGregor and Nine weather presenter Livinia Nixon.

Sister act ... Cate (left) and Bronte Campbell will be among the VIP guests on day two. Photo: Getty Images

Have you spotted a celebrity at the Open or have a tip? Email us.