Nalbandian complained of muscle spasms in his back in a hitting
session at Melbourne Park, the Australian Open venue.
The 26-year-old Argentine player was advised to take two to
three days off and he would assess his condition this weekend
before deciding whether he would play next week at the season's
first major, beginning Jan. 14.
Top-ranked Federer withdrew from the Kooyong event on Monday,
citing a "serious stomach virus," but was back in practice
Wednesday at Rod Laver Arena, the center court at Melbourne Park
where he has won three of the past four Australian Open titles.
He moved freely and showed no signs of discomfort in a short
hitting session after exercising on the new, blue Plexicushion
Federer has previously used Kooyong -- an invitation-only event
stacked with top players attracted by guaranteed matches -- to fine
tune his Australian Open campaigns.
Tournament director Colin Stubs said there was a possibility of
Federer having a match later this week should a vacancy become
Nalbandian was replaced in the field by young Australian Brydon
Klein, but Federer could be brought back if there was a further
"He said he would like the match practice," Stubs said.
"We can slot a match outside the format. Federer, [James]
Blake, [Novak] Djokovic are not out of the equation for a fourth
match outside the bracket."
Kooyong has installed the same Plexicushion surface that the
Australian Open is using this year for the first time, so a chance
on the new surface in match conditions would suit Federer, who had
declared himself fit to defend his Australian Open title.
"I hung around and I definitely think it's going to turn for
the good and I'll be 100 percent, really, before the [Australian
Open] starts," he said at a sponsor's promotion late Tuesday.
He would ask for a Tuesday start at the Australian Open,
although as defending champion and No. 1 seed, he would normally be
allocated a Monday slot.
Fernando Gonzalez, who made last year's Australian Open final,
received a walkover over Nalbandian into the next stage of the
progression-relegation event. He won a warmup match 7-6 (3), 6-4
against Klein for match practice.
Stubs had considered leaving Nalbandian's slot open for Federer
for the remainder of the tournament, but later confirmed Klein
would continue in the relegation side of the draw.