SBW blow for Blues

All Black and Blues centre Sonny Bill Williams is set to undergo knee surgery that will keep him out of action for at least six weeks.

The Blues revealed after training on Thursday that the 33-year-old second five-eight, who is bidding to feature in his third straight World Cup triumph with the All Blacks, faces at least six weeks on the sideline in the wake of "minor" arthroscopic surgery on his knee scheduled for Friday.

Williams sustained the injury against the Stormers a fortnight ago while setting up a try for Blues first five Otere Black and ultimately missed their following match against the Waratahs.

Williams' injury comes at a bad time for the veteran centre as he would likely make it back on the field for the closing stages of the Super Rugby season. The severely limit his chances to prove his fitness and form ahead of the World Cup with the All Blacks boasting a number of midfield contenders.

The Blues had hoped Williams could be fit to face the Chiefs in Hamilton this week, but coach Leon MacDonald confirmed on Thursday that the 33-year-old needs to have a minor operation to fully recover.

‘It’s a big blow, I feel sorry for him. It’s unfortunate for him,’ MacDonald said. ‘The knees have caused him trouble in the past, but he’s pretty driven to make sure he recovers well from this injury and gets back on the field.

‘If he still wants to play later on, he’s the sort of guy who you would never write off. He’s a pretty determined guy, and this year he wants to make the World Cup squad, and be a part of that obviously.’

Williams has been officially withdrawn from the All Blacks "foundation day" in Wellington on Monday and will not be replaced.