Fernando Forestieri is fit for Watford's clash with Birmingham but Matthew Connolly is a doubt.
Striker Forestieri will be added to the squad for the first time in a month after overcoming a knee injury.
Defender Connolly could miss out, however, after he was substituted due to a tight hamstring during Wednesday's 3-1 win at Nottingham Forest.
Joel Ekstrand and Sean Murray remain on the sidelines with long-term knee injuries.
Diego Fabbrini and Lloyd Dyer are ineligible for Birmingham under the terms...