Lomu is the most potent attacking force in the history of the game

Lomu, who has suffered from the kidney disorder nephrotic syndrome, received the kidney from an anonymous donor, thought to be a friend.

His spokeswoman, Bridget Abernethy, said the player had surprised doctors with his speedy recovery.

"He is resting comfortably at his Auckland home and is happy to be out of hospital," Abernethy said.

It will be a number of weeks before doctors can say whether the transplant has been a success.