Japanese star Kei Nishikori has withdrawn from the Australian Open, citing a right elbow injury.
The world No.13, who has not played since a third-round loss to Alex de Minaur at the US Open, required minor elbow surgery in the off-season.
The injury means Nishikori will not travel to Australia. "Unfortunately I have to pull out of the ATP Cup and the Aussie Open," he said.
"Today, together with my team, we have made this decision as I am still not 100 per cent ready (or) healthy to compete at the highest level.
"This decision was not taken lightly as Australia is one of my favourite places to compete.
"Together with my team I will keep working hard to be back on court as soon as possible. Thanks for all the support."
Nishikori, who peaked at world No.4 in 2015, is a four-time Australian Open quarterfinalist (2012, 2015, 2016, 2019) with a 29-7 record at Melbourne Park.