The Blues will be without both Rieko and Akira Ioane for this weekend's Super Rugby Pacific clash with the Brumbies.
Rieko is the worst hit of the All Blacks brotherly duo, with his hamstring strain - which forced him from the field in the early stages of Saturday's 53-26 demolition of the Reds - projected to sideline him for the rest of the regular season.
He'll miss the final round-robin game against the Waratahs on May 28 and is expected to return the following week for the quarter-finals.
The prognosis for Akira Ioane is less severe. His absence is more towards the precautionary side of the scale, taking the week off as part of his recovery from the surgery he underwent to fix the foot injury which ruled him out of the first eight rounds of the competition.
He made his 2022 debut just a fortnight ago in the 22-18 win over the Force at Perth and will make the trip to Sydney to face the Waratahs.
"We're definitely going to miss [Rieko] but at the same time, he's still around," said Blues wing Caleb Clarke. "He's still helping all the boys and we have so much depth in our team that anyone can take anyone's spot
"We feel like the void won't be too big … there's a lot of time for him to recover."
Bryce Heem made an instant impact upon replacing Akira Ioane at Eden Park, crossing for a try just minutes after he took the field, before adding another later in the match. He'll likely pair with Roger Tuivasa-Sheck in the starting midfield against the Brumbies and Waratahs.
Tom Robinson shapes as the replacement for Akira Ioane on the side of the scrum, shifting across from lock to allow Luke Romano to start in the second row.
The form team of the competition, the Blues are essentially a lock to host one of the four quarter-finals at their fortress of Eden Park, with the eight-placed Highlanders shaping as their most likely opponents.
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