Jerome Kaino will experience a disrupted lead-up to the British & Irish Lions Tour to New Zealand after the Blues announced he will undergo knee surgery this week.
The setback means Kaino could miss the Blues' remaining six matches until the international break, giving him little game time between now and the arrival of the Lions.
The loose forward has been key for the Blues in the first nine rounds of the season.
Assistant coach Steve Jackson said he didn't expect the surgery to put Kaino's All Blacks duty in doubt.
"What I can understand is he's going to have a little operation tomorrow which is around 4-6 weeks so I'm pretty sure he'll be fine for the Lions tour.
"He'll get his feet up and [people] normally come back pretty quick from those sorts of operations."
The tourists open the series against the New Zealand Provincial Barbarians on June 3.
They will then play against the Blues in a midweek game on June 7 which could be in Kaino's sights to tune up before the first Test on June 24.
Ruled out of the Blues' match to the play the Brumbies this weekend, Steven Luatua will replace him in the six jersey while Akira Ioane achieves a promotion to start at the back of the scrum.
Young Taranaki lock Leighton Price will potentially earn his Super Rugby debut off the bench after coming in as locking cover during the week.
In the backline, Rieko Ioane will start on the left wing as Sonny Bill Williams and George Moala are named in the midfield while form winger Melani Nanai has been dropped to the bench.
Blues team to face the Brumbies
1. Pauliasi Manu 2. James Parsons 3. Charlie Faumuina 4. Gerard Cowley-Tuioti 5. Scott Scrafton 6. Steven Luatua 7. Blake Gibson 8. Akira Ioane 9. Augustine Pulu 10. Piers Francis 11. Rieko Ioane 12. Sonny Bill Williams 13. George Moala 14. Matt Duffie 15. Mike Collins
Reserves: 16. Matt Moulds 17. Ofa Tu'ungafasi 18. Sione Mafileo 19. Leighton Price 20. Murphy Taramai 21. Billy Guyton 22. Bryn Gatland 23. Melani Nanai
