The home side were denied a point at Ewood Park in the dying seconds on Saturday and will be looking to return to the goalscoring form of earlier in the season.
Leicester's run of six games without defeat came to an end at home to Crystal Palace, a result which knocked them off the Championship top spot.
Zola might look to rejuvenate his attack by bringing in Spaniard Alexandre Geijo for Fernando Forestieri, while Nigel Pearson could stick with a similar team that had been so impressive until the Palace defeat.
Watford: Almunia; Hall, Doyley, Cassetti, Hoban; Fanchone, Yeates, Hogg; Smith; Geijo
Leicester: Schmeichel; De Laet, Konchesky, Morgan, Whitbread; Drinkwater, James, Knockaert; Vardy, Nugent
Sports Mole says: 1-2