Waratahs number eight Wycliff Palu admitted the loss of Dave Dennis to a ruptured anterior cruciate ligament in his right leg is a big blow to the team.
Dennis came off against the Brumbies and had to watch their 36-8 win, with a scan that evening confirming the worst ahead of the season run-in.
"I heard him screaming and I didn't feel too good because I didn't know if it was my fault or what it was," Palu told The Sydney Morning Herald.
"He's our captain and stuff but he's a big part of our team, just having him around. You saw it when he came off, there was a bit of a drop in concentration."
"A key for us this season is the depth we've got. I'm sure whoever steps up will do the job."
The Waratahs host the Highlanders next Sunday.