A rare eye condition that needs surgery will delay the return to training of two-time Group One winner Te Akau Shark.

Trained in New Zealand, Te Akau Shark has been spelling in NSW since a successful autumn that netted elite-level wins on both sides of the Tasman.

"Whilst spelling, we further investigated an eye irritation of Te Akau Shark's that we have managed successfully," Te Akau Racing principal David Ellis said.

"Expert international equine eye surgeons, together with our Sydney veterinary team, have decided it is in Te Akau Shark's best future racing interests to undergo an optic implant surgery.

"His issue is a rare one and the procedure has been scheduled for this week."

Ellis is unsure when last year's WS Cox Plate placegetter, trained by Jamie Richards, will return to racing.

Te Akau Shark broke through for his first Group One win in the Waikato Sprint in New Zealand before scoring an explosive victory at the same level on his return to Australia.

Standing up his rivals a huge start, Te Akau Shark overpowered a field of weight-for-age horses in the Chipping Norton Stakes at Randwick.