Emma Raducanu withdrew from her opening match at the United Cup due to an unknown injury - but Great Britain captain Tim Henman is hopeful she will not miss the entire tournament.

Raducanu, 23, was scheduled to play against Japan's Naomi Osaka in Perth on Sunday, only to pull out and be replaced by Katie Swan in the women's singles.

Henman told Australian broadcaster Nine of Raducanu, who has not played since ending her 2025 season in October after a bout of illness in China: "I've got to be honest, she was very, very close.

"It was not any easy decision. She had been building up and practising really well. I don't think she is necessarily out of this tournament just yet."

Billy Harris - a replacement for the injured Jack Draper for GB - beat Japan's Shintaro Mochizuki 7-6 (6-4) 6-3 before Swann stepped up to face four-time Grand Slam champion Osaka.

In the United Cup, 18 countries are split into six groups of three and play the other teams in their pool once each before the six group winners and two second-placed teams reach the quarter-finals.

Each tie consists of one men's, one women's and one mixed doubles match, with Olivia Nicholls and Neal Skupski poised to represent Great Britain in the latter.

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