Marlon King returns from suspension to face his former club but the striker's comeback does little to ease Coventry's lengthy injury problems.
King is ready to figure in caretaker boss Andy Thorn's starting XI having served a four-match ban for his dismissal at Bristol City, as attention switches back to on-field matters for the Sky Blues following a turbulent week behind the scenes.
The versatile Martin Cranie (hamstring) and striker Clive Platt (back) are struggling while midfielder Carl Baker will be assessed having rolled his ankle in training during the international break.
Defender and stand-in skipper Richard Wood is the latest to join a growing list of absentees having been ruled out for six weeks with a groin strain sustained in the 2-1 defeat at Preston.
Wood joins captain Lee Carsley (Achilles), centre-backs Ben Turner (knee) and James McPake (back) and midfielders Gary Deegan (knee) and Isaac Osbourne on the sidelines.
Watford will be without defender Adrian Mariappa for the trip.
Mariappa was sent off in the closing stages of the 2-1 defeat at Middlesbrough before the international break and will serve a one-match ban, so Dale Bennett could come into the side.
Right-back Lloyd Doyley is still suffering with the knee injury he sustained against Ipswich earlier in March and is a doubt but Lee Hodson is fully fit after an ankle injury.
On-loan midfielder Danny Drinkwater is back at Vicarage Road after receiving treatment for his thigh injury at parent club Manchester United and could feature.
Midfielder Stephen McGinn is a long-term absentee with a serious knee injury as the Hornets look for three more points.