Blues coach Pat Lam says it's a massive blow to lose Tony Woodcock for tomorrow night's game against the Reds at Eden Park.
The loosehead prop has been one of the Blues' best players since making a late start to this season's campaign and would have one of the key players tomorrow, but he picked up a calf strain in training yesterday and this morning was officially ruled out of contention.
Hooker Keven Mealamu is also out injured with a calf strain and Lam said he is always worried about those types of injuries with front rowers.
"It's a massive one," Lam said of this blow.
"I said after the game [against the Highlanders] he was the player of the game, not just for the scrums but the physicality he brought around the field.
"We talked about real aggressive, wrestling defence and he was responsible for two or three turnovers, just throwing his body around the line.
"But again we've just got to roll with the punches and move on, focus on the game.
"If it was the hamstring or another muscle he possibly could have played, but with a calf there is the scrummaging and the load," Lam said.
"It is similar to Keven. The medical staff are always conservative and at this stage they're saying hopefully [back] for next week."
Mealamu is also down to be back for the Blues next week, against the Hurricanes, but Lam said he doesn't want to take any risks in rushing him back early.
"For front rowers it's really tough on their calves," he said,
"We want to make absolutely sure with Kevvy, we don't want him to come in, play a couple of games and then have the same problem, we really want to have that cured, not only for us, but also his sake."
Woodcock will be replaced by Tevita Mailau in the starting team while either Pauliasi Manu or Angus Ta'avao will come onto the bench.
In other changes, Chris Lowrey and Benson Stanley drop to the bench with Daniel Braid and Rudi Wulf taking their respective positions in the starting line up.
Meanwhile, Lam was pleased that Piri Weepu had made enough progress with his fitness to make it back into the starting team.
'He has made massive gains, or losses if you like!" said Lam, joking about the 5kgs he has lost over the past couple of months.
"He's into the 90s now and out of the 100s which is great and his skin folds have come down quite a bit.
"We saw the impact he made last weekend and that's all in relation with the work he's been tirelessly doing behind the scenes. He has done well enough to get a start."
Blues: Hadleigh Parkes, George Moala, Rene Ranger, Ma'a Nonu, Rudi Wulf, Gareth Anscombe, Piri Weepu, Peter Saili, Luke Braid (capt), Daniel Braid , Filo Paulo, Ali Williams, Charlie Faumuina, Tom McCartney, Tevita Mailau. Reserves: James Parsons, Angus Ta'avao, Liaki Moli, Chris Lowrey, Alby Mathewson, Michael Hobbs, Benson Stanley.
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