All Blacks star Sonny Bill Williams will miss Auckland Blues' Super Rugby match against the Central Cheetahs as he struggles to shake off concussion, the club said on Wednesday.
Williams left the field for a head injury assessment during the Blues win over the NSW Waratahs last weekend and never returned.
Coach Tana Umaga said the two-time World Cup winner was making progress but was not fully recovered, making it "prudent" to rest him for Friday's match.
"He's much improved but he's got to go through the protocols until he is symptom free, so that probably wouldn't have him right for this weekend," Umaga told reporters.
In more positive news for Umaga's side, Test lock Patrick Tuipulotu was cleared to play after four weeks out with a back injury.
Williams is among a string of All Blacks under an injury cloud ahead of the British and Irish Lions tour starting next month.
They include Kieran Read, Jerome Kaino, Ben Smith, Dane Coles, Nehe Milner-Skudder, Elliot Dixon, Lima Sopoaga and Tawera Kerr-Barlow.