The Blues suffered a setback ahead of Saturday's clash with the Brumbies in Auckland when flanker Steven Luatua was sidelined through injury.
Luatua, who was one of eight Blues players called into the All Blacks training squad earlier this week, injured his neck during last week's loss to the Crusaders.
"He banged up his neck last week and it hasn't freed up," said Blues boss Sir John Kirwan.
"We felt that he'd be playing at 80 per cent rather than a hundred and we'd like to put the athlete first. I made the decision and he's not very happy about it but I've taken him out of the team.
"He's got no real damage, he's just had a pretty bad knock to the neck and shoulder and will be available for us next week."
As a result Brendon O'Connor is promoted from the bench to start at blindside flanker.
Tighthead prop Angus Ta'avao tweaked his knee during training on Tuesday and has been bracketed with Sam Prattley. Ta'avao will have a run at today's training session, with a call to be made on his availability later in the week.
The only change to the back-line comes at second five-eighths where Francis Saili starts ahead of Jackson Willison.
"Jackson and Francis have been our form guys," Kirwan added.
"I think Francis brought a real excitement to the game last week when he came on. We need him to step up with his vision and his verbals helping Noaksey out, looking up and making the right calls but if he can bring his excitement and footwork then we'll be really happy."
Blues: 15 Charles Piutau, 14 Frank Halai, 13 Rene Ranger, 12 Francis Saili, 11 George Moala, 10 Chris Noakes, 9 Piri Weepu; 8 Peter Saili, 7 Luke Braid, 6 Brendon O'Connor, 5 Ali Williams (c), 4 Culum Retallick, 3 Angus Ta'avao/Sam Prattley, 2 Keven Mealamu, 1 Tim Perry.
Replacements: 16 James Parsons, 17 Sam Prattley/Ofa Tu'ungafasi, 18 Anthony Boric, 19 Kane Barrett, 20 Jamison Gibson-Park, 21 Baden Kerr, 22 Jackson Willison.
Date: Saturday, May 25
Venue: Eden Park Stadium, Auckland
Kick-off: 19.35 (07.35 GMT)
Referee: Lourens van der Merwe (South Africa)
Assistant referees: Jonathon White (New Zealand), Nick Briant (New Zealand)
TMO: Glenn Newman (New Zealand)