Mariappa back for Hornets
Adrian Mariappa returns from suspension to provide Watford with an almost fully-fit squad for their trip to Peterborough.
Mariappa missed Tuesday's 2-2 draw at Brighton due to a one-match ban following his dismissal in last weekend's clash against Hull.
Fellow centre-back Martin Taylor overcame a facial injury to start at the Amex Stadium, meaning manager Sean Dyche now has a welcome selection dilemma in defence as to who partners Nyron Nosworthy.
Long-term injury victim Stephen McGinn (knee) is the only absentee at London Road, with the midfielder likely to need more reserve-team action before being considered for selection. Although it remains to be seen whether he could make the bench between now and the end of the season.
The Hornets have drawn each of their last three matches and are winless in four, yet they have tasted defeat just once in their previous 11 and are unbeaten away from home since mid-February.