The Sydney International has been rocked by the withdrawal of the top two men's seeds with French duo Jo-Wilfried Tsonga and Richard Gasquet pulling out of the Australian Open lead-up event.
World No.8 Tsonga, who was to be top seed at Sydney Olympic Park, suffered a hamstring injury while representing France in the Hopman Cup on Friday night.
"Unfortunately Jo-Wilfried Tsonga sustained an injury in Perth and has been forced to pull out of the Apia International Sydney with a left hamstring injury," tournament director Craig Watson said.
"We wish him a speedy recovery and all the best for a successful Australian Open."
Tsonga - the 2008 Australian Open finalist - was to have been replaced as top seed by compatriot and world No.10 Gasquet before he too pulled out due to personal reasons.
The men's draw for the Sydney International will take place at midday on Saturday.
Australians Matt Ebden, James Duckworth and John Millman have been granted wildcards into the men's draw.
"I am thrilled to receive a wildcard and look forward to returning to Sydney where I had such a great experience last year," Ebden said.
Brisbane-based Millman started his year in great form, winning through qualifying at the Brisbane International before eventually losing to world No.4 and US Open champion Andy Murray in a tight three-set encounter in the second round.
The 23-year-old Millman will make his second appearance in Sydney, his first in the main draw singles.