Blackburn's former England goalkeeper Paul Robinson will have a scan to determine the extent of his calf injury.
Robinson lasted only 13 minutes of the 1-0 Carling Cup victory against Everton before being replaced by Jason Brown.
However there is still an outside chance he could face Newcastle on Saturday at St James' Park.
Manager Paul Ince said: "Paul seems to have run over a black cat as he has had a lot of injuries recently.
"He is going to have a scan and fingers crossed he will be ready for Saturday. Having said that, Browny came in and looked assured and steady."
Swedish full-back Martin Olsson scored the only goal of the game and his first for the club to seal Blackburn's place in the fourth round.
It came after a neat one-two with former Liverpool striker Robbie Fowler, who was making his debut.
Fowler played a full 90 minutes for the first time in 10 months following a hip operation while at Cardiff.
Ince was delighted with the 33-year-old's performance and that of veteran midfielder Tugay.
Ince said: "The two old men were different class. Robbie was champing at the bit and keen to prove a point.
"I played him in a slightly deeper role and he did ever so well. He never lost a ball and had a couple of chances.
"He made a difference and showed a lot of lovely touches. He is a natural goalscorer and you do not lose it. The signs are good."
Meanwhile David Moyes sympathised with supporters who booed Everton off following the 1-0 defeat.
James Vaughan did find the net in the second half but his effort was ruled out for an infringement.
Everton boss Moyes said: "They were entitled to do that because we did not play well enough. It was deserved.
"My reaction is whatever the supporters did they were right to do so."