Rafael Nadal, Novak Djokovic and Andy Murray all have injury issues, leaving Roger Federer on track for Australian Open glory.
There is work to be done for Andy Murray, who admitted he was off the pace in a practice match with Roberto Bautista Agut in Abu Dhabi.
Elbow pain has forced Novak Djokovic to pull out of the exhibition event in Abu Dhabi ahead of the Australian Open.
At the age of 36 Roger Federer has no thoughts of retirement as he prepares to defend his Australian Open crown in the new year.
There were contrasting fortunes for the Mubadala World Tennis Championships' late replacements Kevin Anderson and Andrey Rublev.
Roger Federer is curbing expectations ahead of the 2018 season after touching down in Perth for the Hopman Cup.
Rafael Nadal could head into the Australian Open without playing a lead-up tournament after withdrawing from the Brisbane International.
Lessons have been learned from a "roller-coaster ride" in the last 18 months for Novak Djokovic, according to the 12-time grand slam winner.
Novak Djokovic looked a shadow of his former self last year, but a break can enable him to return to the peak of his powers.
Jo-Wilfred Tsonga will give himself extra time to recover from injury with the Australian Open fast approaching.