Bristol City midfielder Marvin Elliott is a major doubt for the Ashton Gate clash with Colchester.
Sean O'Driscoll's men are still searching for their first three-point haul of the season and may have to manage without the Jamaica international who has a groin problem.
Aden Flint and Joe Bryan came through the midweek Capital One Cup defeat with Southampton unscathed after slight niggles, although Flint is just one yellow card away from serving a one-match ban.
On-loan Derby defender James O'Connor is likely to need thigh surgery and faces months on the sidelines, leaving O'Driscoll hunting for a new defender, ideally before the home game against the U's.
Colchester manager Joe Dunne has a mountain of injury problems ahead of the trip to winless Bristol City.
Goalkeeper Mark Cousins (foot), defenders Ryan Dickson (illness), Josh Thomson, Tom Eastman (both ankle) and Mason Spence (hamstring), midfielder Tosin Olufemi (thigh) as well as forwards Gavin Massey (hamstring), Sanchez Watt (thigh) and Drey Wright (knee) are all absent.
Conor Hubble (dead leg) is struggling but has a chance of making it while Daniel Pappoe serves the second game of a three-match suspension.
A rare piece of good news for boss Dunne sees influential defender Magnus Okuonghae return from suspension.