Blues coach John Kirwan is on the hunt for a new lock after being forced to release the injured Culum Retallick.
Retallick, 29, damaged the anterior cruciate ligament in his right knee during training four weeks ago, with Kirwan revealing today that the 1.98m second rower's season is over.
"We've taken Culum out of the squad and it was a really sad thing to do,'' Kirwan said.
"He'll be a big loss for us. Today we have to do that official paper work. The hardest thing about Culum [going] is replacing him because he's a big, tall man and he's got a lot of experience so when you look around to replace that it's pretty difficult. We're taking a little bit of time with it and making sure we get those decisions right. We should have a decision made by the end of the week.''
Tom Donnelly, 32, who has played for the Highlanders and Crusaders, will begin his first season at the Blues ranked as their No1 lock.