Colchester boss John Ward confirmed striker Ashley Vincent will undergo a scan on the knee injury suffered against Wycombe.
Vincent opened the scoring in the 24th minute, slamming the ball high into the net from eight yards following Michael Rose's excellent cross, but faces an anxious wait before learning the full extent of his injury.
Ward said: "It's a knee injury - his left knee was rocked by the challenge and he'll probably have a scan on that on Monday.
"It's a shame for him that he's picked up his injury and we've had to switch things around, but you're never going to get through the season with only 11 starting players."
Ward added: "There was a heck of a lot of good things to come from that football match.
"We had a super game against Wycombe (in the Carling Cup) on Tuesday where we went toe-to-toe with them. But we played some excellent football in the first half and you have to respect what Wycombe have done."