Novak Djokovic is in talks with lawyers about suing the Australian government for A$6 million over "ill treatment" during his last stay in Melbourne.
The Serbian tennis star, 34, claimed he had a visa exemption but was deported before the Australian Open.
Insiders say the damages figure includes the $4.35 million in prize money the World No . 1 expected to have won.
A source close to his agent Edoardo Artladi said: "It's well known that Novak and his family feel he was poorly treated in the quarantine hotel in Melbourne. His mother revealed how it was full of fleas and maggots. He was kept a virtual prisoner."
Lawyer Toma Fila added: "He was subjected to humiliating treatment. He should sue."