The Blues have lost both of their first-choice halves to injury after Piri Weepu was forced out of their tour of South Africa.
Veteran All Black Weepu has failed to recover from a rib injury sustained during the 22-20 loss the Sharks in Durban on Saturday.
He will miss Saturday's crucial match against the Cheetahs in Bloemfontein on Saturday, along with fly-half Chris Noakes, who was ruled out a day earlier with a thigh injury.
The pair are to fly home for treatment.
Halfback Wayne Ngaluafe, who made his Blues debut against France last month, is to join the squad as cover for Weepu while utility back Marty McKenzie is replacing Noakes.
The eighth-placed Blues need to beat the sixth-placed Cheetahs to have any chance of reaching the Super Rugby play-offs.