Paul Simpson admitted initial signs were not good on the knee injury that forced Callum Guy out of action at Barrow.
The Carlisle United captain had to be substituted after just 19 minutes of the Blues’ 2-1 victory.
Guy was later on crutches as he took a seat next to the away dugout to watch the rest of the game.
Manager Simpson said it was too soon to know the full extent of the problem.
But he said it did not look too promising at first glance.
“He jarred his knee – I don’t know how serious it is, but he’s struggling a little bit at the moment,” said Simpson after the game.
“I think he’s been put on crutches at the end of the game, more as a precaution and not the fact that we know what it is.
“We’ll see how he is come Monday and we’ll assess it from there. At this moment it doesn’t look particularly good.”
Guy was hurt in a fair 50-50 challenge with Barrow’s Tom White and after briefly trying to run off the injury, had to admit defeat.
He was replaced by Corey Whelan, who also took the armband for the remainder of Carlisle’s victory.
Simpson said the way the team adapted to the blow of losing their skipper was vital.
“It’s massive,” he said.
“I said this at the start – it isn’t gonna be 11 players who get us through, we’re going to need the full group.
“There are players who’ve been left out here like Mitch Roberts…this was a game I wanted to win so I went with more attackers on the bench because I felt it was really important.
“Mitch missed out because of that. I had to speak to him once Jack [Armer] told us he wasn’t feeling well and said, ‘You get ready, if he’s not right in the warm up I’m changing it and you need to be ready’.
“There’s a chance these lads will play a part between now and the end of the season and you have to be ready, as Danny [Devine] was on Tuesday, as Corey was here, to come on and affect a game.”
Simpson said United’s win came despite the squad being disrupted with illness during the week, keeper Magnus Norman ruled out of the squad as a result and other players affected – with others nursing knocks.
“Corey took a horrendous whack in training on Friday morning and, being honest, he was a doubt, but when I made the substitution I forgot about him having a swollen foot,” Simpson said.
“I’ve just seen it now and it’s not pretty.
“I think all of the players have shown character. We had a bit of a bug going through the camp – Jon Mellish missed a day with it, and with issues going on with his [pregnant] partner, and Omari Patrick was struggling before Tuesday night.
“Jack Armer was struggling [on Saturday] with it, Magnus Norman is missing with it, and we’ve had to get on and deal with it.
“Because of that the club have decided to reactivate the red zones in the changing room areas to make sure we don’t get any risk of infection spread.
“We’ve got to make sure we’re really focused over the week and that we approach things properly so we’re ready to go again.”
READ MORE: VERDICT: Paul Simpson's transformed Carlisle United keep on rising at Barrow AFC
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