Jonah Lomu's family have asked for privacy after the rugby legend was admitted to hospital because of a health scare relating to his kidneys.
Lomu is in a stable condition in the renal and liver transplant ward at Auckland City Hospital.
A hospital spokesman would not comment further on his condition because his family had requested privacy while he was treated.
The former All Black superstar was diagnosed with a kidney disorder called nephrotic syndrome in 1995.
He received a kidney transplant in July 2004 after ZM radio personality Grant Kereama became his donor.
Lomu appeared at the Rugby World Cup opening ceremony as the hero of rugby for players like 13-year-old Ethan Jack Bai.
Ethan Jack's dad Brenton said Lomu was in good shape during the opening ceremony.
"EJ hung with him quite a bit before the opening ceremony. He danced with the boys and went through the ceremony a couple of times in practice.
"He was animated and relaxed. He really enjoyed it and I was taken by him by how able he was and approachable,'' Bai said.
Prime Minister John Key said today he was unsure of Lomu's condition, but that he was thinking of popping in to Auckland Hospital to visit.
"Obviously we're very saddened to hear he's been unwell, but I don't have any update.''