City could require a new skipper for Tuesday's match at Colchester United after Bantams boss Phil Parkinson confirmed that Gary Jones is currently struggling to prove his match fitness due to a virus.
Jones missed training this Monday due to the illness and was actually troubled by the bug during Saturday's match at promotion-chasing Brentford.
Parkinson said: "Gaz has been laid low with a virus for the past few days and looks doubtful for Tuesday.
"He wasn't 100% at Brentford and he hasn't improved much since then.
"The intensity of the game and the heat of the afternoon won't have helped but it is a credit to Gaz that he carried on and didn't throw the towel in at half time.
"He has been immense this season and it typical of him to keep going when he perhaps should have just said he was struggling.
"We have players keen to come in and impress if Gaz doesn't make it though. We changed things around a bit around this time last year to try and keep things fresh, we might have to do it again this season as well."
The duo of Andrew Davies and James Hanson will both also need to be assessed pre-match after the pair missed the Brentford match due to injury.
Parkinson said: "Dava is a lot better today (Monday) but Hanson is still not quite right.
"Both will be travelling with us to Colchester and we will assess them on the morning of the game.
"We will be doing some training in the morning in preparation for the game and hopefully they can play some part in that."