Serena Williams accused of 'cashing in' on Meghan Markle friendship

Nina Agdal, Serena Williams and Meghan Markle participate in the DirecTV Beach Bowl in 2014. Photo / Getty

It's the kind of publicity most fashion labels can only dream of.

On Wednesday, Meghan Markle arrived in Dubbo wearing the $203 'Boss' oversized blazer from Serena Williams Collection.

Like other lucky designers in her situation, Williams, who is a close friend of the Duchess of Sussex, quickly took to social media to publicise the fact that Meghan was wearing her blazer.

Sharing a photo of herself wearing the blazer, Williams wrote: "The face you make when you and Duchess of Sussex Meghan have matching @serena blazers #BeSeenBeHeard Link in bio to shop the collection!"

Williams' post prompted a mixed reaction from her followers with some accusing the tennis star of taking advantage of her relationship with Meghan.

"Cashing in on your friendship this way is terrible. Serena should not be using a member of the British Royal Family as a clothes horse for her range," one person commented.

View this post on Instagram

The face you make when you and Duchess of Sussex Meghan have matching @serena blazers 😍 #BeSeenBeHeard Link in bio to shop the collection!

A post shared by Serena Williams (@serenawilliams) on Oct 16, 2018 at 5:51pm PDT

"Well this goes against Royal protocol," another commented.

But others argued it was just a case of "friends supporting friends" and it was nice to see Meghan wearing Williams' blazer.

I hope Kensington Palace or Duchess Meghan asks Serena to remove the posting. It's different when a company or person who doesn't have a personal connection to the Royal uses it as a marketing tool, but considering how close Serena and her are, it doesn't sit well with me.

— A (@Lady_AJM) October 17, 2018

A photo of Meghan wearing Williams' blazer features prominently on the fashion label's website and has already sold out online.

Williams and Meghan have been friends since 2010 after meeting at a Super Bowl party, with the Suits star writing on her blog The Tig that the pair "hit it off immediately".

"Taking pictures, laughing through the flag football game we were both playing and chatting not about tennis or acting but about good old fashioned girly stuff," Meghan wrote.

In an interview with The Sunday Project in September Williams told Lisa Wilkinson they had maintained a close relationship.

"We were actually just texting each other this morning," she said. "We have known each other for a long time, but we really are relying on each other a lot recently."