British number four Laura Robson has been forced to cancel a training trip to Las Vegas after suffering a stress fracture of the left shin.
The 17-year-old was due to spend three weeks at a camp with Andy Murray's occasional coach Darren Cahill and Andre Agassi's ex-trainer Gil Reyes.
However, Robson has targeted January's Australian Open for her comeback.
"I'm unable to go to Vegas but back in action in a few weeks so prep for Aus will start then," she said on Twitter.
A hip injury ruled the Australian-born left-hander out for the early part of 2011 but she reached the second round of the final two Grand Slams, Wimbledon and the US Open.