Emma Raducanu withdrew from her tie against Naomi Osaka as Great Britain started their United Cup campaign against Japan in Australia.
The British number one has not played since October and no reason was given for her pulling out against Osaka in Perth, in the lead up to the Australian Open, which begins in Melbourne on 18 January.
"I have to be honest, she was very close," GB team captain Tim Henman told Australian broadcaster Nine.
"It wasn't an easy decision. She had been building up and practising really well. But we just felt this morning it was a little bit too early.