Magnus Okuonghae could miss the rest of the season after it was confirmed he has suffered a ruptured Achilles tendon.
The Colchester United skipper is set to undergo surgery later this week, after suffering the injury in the 1-0 defeat against Coventry City, on Saturday.
U's boss Tony Humes said: "It's a big blow all round.
"It's a major injury for Magnus and it's sad that it looks like he will miss more or less the rest of the season.
"It was an innocuous incident - he went up to head the ball and the mechanics caught him out somewhere.
"There was no contact or anything like that."
Colchester are now likely to dip into the loan market as a result of Okuonghae's injury.
For more on this story and all of the latest Colchester United news, see Tuesday's Daily Gazette.
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