Ma’a Nonu returns for a heavyweight battle with All Blacks Test rival Sonny Bill Williams when the struggling Blues meet the Super Rugby-leading Chiefs on Saturday.

Nonu’s recall at inside centre is among six changes to the Blues starting team from last weekend’s 27-20 loss to the Highlanders.

Playing in a team that’s second last on the ladder, Nonu faces a big task to hold his Test spot ahead of Williams who has been outstanding in the Chiefs midfield in 2012.

Blues coach Pat Lam also brought back veteran All Blacks lock Ali Williams for the showdown with the neighbouring Chiefs in Auckland.

But World Cup halfback Piri Weepu will continue to warm the bench while Alby Mathewson starts again.

Nonu’s return allows Michael Hobbs to move one place in to take over at five-eighth from the injured Gareth Anscombe.

In other personnel changes, outside backs Rudi Wulf and Rene Ranger return from injury, with Wulf slotting in at fullback in his 50th game for the Blues.

Lachie Munro is promoted from the reserves to the right wing, while a refreshed Daniel Braid is back at openside flanker.

Blues: Rudi Wulf, Lachie Munro, Francis Saili, Ma’a Nonu, Rene Ranger, Michael Hobbs, Alby Mathewson, Luke Braid (capt), Daniel Braid, Steven Luatua, Ali Williams, Liaki Moli, Tevita Mailau, James Parsons, Tony Woodcock. Res: Tom McCartney, Angus Ta’avao, Filo Paulo, Peter Saili, Piri Weepu, Hadleigh Parkes, David Raikuna.