Serena Williams
Williams won her seventh Australian Open title in Melbourne. Getty Images

Winner stays on never meant so much after 23-time grand slam singles champion Serena Williams stunned two unsuspecting amateur male players by challenging them to a game. The American was out walking with fiancé and Reddit co-founder Alexis Ohanian when she decided to surprise the fans, with the footage posted via her Snapchat account.

The 35-year-old, who won her seventh Australian Open crown in Melbourne in January, was wandering by a court with Ohanian and dog Chip when she came up with the idea. "I'm thinking about asking these guys if I can have a hit just to see their reaction," she said, before approaching the pair.

Williams is heard asking "can I play the winner?" before taking to the court wearing soft boots, a far cry from the regulation footwear she would wear on the WTA Tour. Footage thereafter of the trio playing together is sparse but she stays to chat and pose for a photo with the overwhelmed players.

The Florida-based Williams signs off by warning fans: "The moral of the story is, you'll never know when I will be coming to a tennis court near you". There is no clear indication the stunt is linked to a commercial or sponsorship obligation.

World number one Williams was named as the world's best paid sports woman last year, earning $28.9m (£23.2m) in 2016, but is not the only tennis player to find a unique way to reach out to their fans. Earlier in February, Canada's Eugenie Bouchard went on a date with a university student after losing a bet on the result of the Super Bowl, which saw the New England Patriots come back to beat the Atlanta Falcons.