The U.S. Tennis Open champion Juan Martin Del Potro will stand in for Roger Federer at the invitational Kooyong Classic in January if the Swiss world number one decides against defending his title.
Federer thrashed compatriot Stanislas Wawrinka to win the title earlier this year, but is in doubt for the January 13-19 Australian Open warm-up event due to a shift in priorities having become the father of twin girls.
He's been a fixture at Kooyong since 2004 and has used it as a springboard to three Australian Open titles but the 15-times grand slam champion has indicated he may scale back his programme.
If he decides against playing at Kooyong, or another player withdraws before January 13, the tournament director Colin Stubs says del Potro will step into the field.
