The Blues had feared Rush would be out until the new year.

But Blues boss Dai Young said: "He's had his operation and thankfully it was nowhere near as bad as first feared.

"I think he's going to be out for at least six weeks. The prognosis is he's back sometime in September."

Young says the Kiwi number eight will be allowed to fully recover before returning to regional action.

"It's still a blow, but it's nowhere near as bad as we expected, really," said Young.

"We won't rush him back. Player welfare is hugely important. He's had the operation and the specialist was really pleased with it.

"It's now just a matter of his rehabilitation and when we feel he's ready."