His replacement, Simon Ford, limped out after less than 20 minutes action though with a hamstring problem. Wingback Jason Crowe was drafted into the centre of defence and despite a fine game, may struggle against more physical strikers.
It seems unlikely that either Edwards or Ford will return for the Tuesday night clash with Notts County. Groves may well avoiding risk playing Crowe in the centre again with County's attack, including Town summer target Clive Platt, a much more physical threat than Colchester's.
Rookie defender Greg Young is most likely to be drafted in after some steady performances from the bench of late.
Groves will hope that at least one of Ford and Edwards will recover in time for Saturday's visit to Barnsley.