Serena Williams oozes power and trendy in Berlei at Myer in Melbourne on Thursday following rumors that she's separating with "boyfriend" coach Patrick Mouratoglou.

Serena Williams is the face of Berlei and she wore a patterned sports bra along with a purple trim underneath a black high-waisted skirt and black blazer.

The lingerie company described itself as "dedicated to engineering sports bras that offer women the best protection when they're exercising," and that it's the only "bra manufacturer that works with the Australian Institute of Sport (AIS) to deliver a product that actually reduces breast bounce."

According to test results by the AIS, Berlei's Electrify Underwire sports bra "can reduce breast bounce by up to 50%."

"My mum first discovered Berlei while on a trip to Australia almost 10 years ago and I have been wearing their bras ever since - for every tennis match without fail," she said per Mail Online.

Serena Williams has been hounded by rumors that she's dating her coach Patrick Mouratoglou.

Earlier article from KpopStarz speculated that Serena Williams will drop her rumored boyfriend Patrick Mouratoglou as coach after her beatdown from Eugenie Bouchard during their singles match in the Hopman Cup in Perth, Australia.

"After Serena's loss to Eugenie Bouchard, she may not be feeling so cozy with her coach slash boyfriend," it said.

The world's no. 1 has always denied that she's dating anybody, her coach Patrick Mouratoglou included. But the rumors keep on hounding the couple everywhere they go.

At the start of the year, Serena Williams had a selfie with her coach, the photo of which was published on Daily Mail, as they arrived in Perth for the Hopman Cup. Her rumored boyfriend Patrick Mouratoglou previously admitted that 2014 has not been a great year for Serena Williams due mostly to her injuries but they are looking to bounce back with stronger performances going forward.