Emma Raducanu withdrew from the first tournament of the new season due to injury.
The 22-year-old was forced to withdraw from the ASB Classic in Auckland due to back problems.
“I did my best to be ready,” he told Raducan on television WTA website. “I love Auckland and the fans here, but unfortunately I'm having problems and I won't be ready in time.”
The tournament was to be Radučanu's first since hiring renowned fitness trainer Yutaka Nakamura.
The former British number one has been dogged by fitness issues since her stunning 2021 US Open triumph, missing two months at the end of last season with a foot injury.
Raducanu trained at the National Tennis Center in London after helping Britain reach the semi-finals of the Billie Jean King Cup last month before going to work in the warm weather over Christmas.
She was seeded sixth in Auckland and was due to meet 20-year-old American Robin Montgomery in her opening match. Former Grand Slam champions Naomi Osaka and Sofia Kenin are also taking part in the tournament.
It's another blow for Radučana, as this latest injury problem won't help her in her preparations for the first Grand Slam of the year, the Australian Open, which starts on January 12.