Chester has been playing through the pain for Villa, and has been left unable to train.
The Welsh centre-back been struggling since December with a knee problem, and Villa could go back into the transfer market as a result.
Dean Smith has already brought in Lovre Kalinic and Kortney Hause this month, as they have looked to strengthen their backline.
However, Villa are not fully satisfied that they have enough quality at the back, even at this stage.
The claret and blues could now look to snap up another defender, as they aim to tighten up in defence.
Yannick Bolasie’s loan at Villa was terminated yesterday, which should free up some wages to bring in another new face.