Phil Bardsley admits Lee Cattermole will be a big loss for Sunderland should he miss game time with the injury he picked up against QPR.
Cattermole, the Sunderland captain, recovered from a knee injury in time to start Tuesday night's game but was forced off after just six minutes after damaging the other knee in an early tackle.
He is currently undergoing treatment and Bardsley revealed the midfielder's angst as he was forced to watch the remainder of the draw from the stands.
And, should he end up missing for a period of time, Bardsley says the onus is on the other members of the squad to make the transition as smooth as possible.
"I am good friends with Lee and he is really disappointed because he put all his efforts into playing that game," he said.
"It's disappointing for Lee and a big loss for us because the energy he puts into the team gives us a massive lift.
"However, we've got other players who will need to step in and fill in for him."
Meanwhile the squad are in the thick of preparations for Sunday's game against Norwich at Carrow Road.
City's 1-1 draw at Southampton on Wednesday night extended their unbeaten run to seven Barclays Premier League games.
But Bardsley has taken heart from Sunderland's performances in their last two away matches and is hoping for a repeat of the win at Fulham in their last road outing.
"Norwich is a difficult place to go but we have to build on the point against QPR and start getting results," he said.
"A draw wasn't really what we wanted [in the last game] but it's a start.
"At both Fulham and Everton before that the lads were terrific so we'll go to Carrow Road and have a right go."