Melbourne - Argentine Juan Del Potro was Tuesday drafted into standby for Roger Federer as the pre-Australian Open AAMI Classic waits on the Swiss to finalise his 2010 playing schedule. US Open winner and world number-five Del Potro will take over as eighth man at the key preparation event at Kooyong club in case Federer opts out of the field.
The world number-one has played for five of the last six years, missing only 2007 with his glandular fever.
Federer has asked organisers to hold him a spot for the January 13-16 warmup. His plans may be somewhat changed from now on after the summer birth of his twins.
The Swiss will start the New Year in Abu Dhabi at a six-man exhibition with Rafael Nadal before travelling to Australia.
Federer won at Kooyong last January over Davis Cup teammate Stan Wawrinka, then played the Australian Open final a fortnight later against Nadal.
"If Roger decides against playing at Kooyong, or another player withdraws before January 13, Juan Martin will step into the field," said Kooyong boss Colin Stubs. "I'm delighted that such strong back-up plans have been put in place."
Federer has won three Australian Open titles on the back of Kooyong preparation and would likely not want to change a winning programme.
The remainder of the field is comprised of Novak Djokovic and losing Australian Open finalist to the Serb last year, Jo-Wilfried Tsonga, plus French Open finalist Robin Soderling, former Melbourne finalist Marcos Baghdatis, Spain's Fernando Verdasco, German Tommy Haas and Fernando Gonzalez of Chile.
