When Kyrgios returned to action at the recent Brisbane International after an 18-month absence, it completed a comeback which even his wrist surgeon doubted was possible.

Kyrgios suffered a full rupture of the scapholunate ligament, which often leaves patients unable to regain normal function even after surgery.

"In the past, our ability to restore such a wrist after such severe injuries has been unreliable - let alone getting someone back to high level sport," Dr Michael Sandow, who is regarded as one of Australia's leading wrist surgeons, told BBC Sport.

"His return to tennis is better than we could have hoped for."

A 3D modelling and animation technique - developed over 20 years at the University of Adelaide and the Wakefield Orthopaedic Clinic where Dr Sandow works - allowed the surgeon to use an innovative and complex repair technique on Kyrgios.

The drilling of the wrist bones and use of artificial ligaments enabled the joint to be realigned.

Kyrgios picked up a racquet again nine months after the surgery in September 2023.

"As a surgeon you hold your breath when your patient is pushing the boundaries of competitive sport," added Dr Sandow.

"Nick's progress so far has been a massive team effort and we are looking forward to him pushing deeply in the Australian Open."