Watford opened their pre-season campaign with a 4-0 win over non-League outfit St Albans City in Quique Flores' first game in charge.
Nigerian Odion Ighalo netted a brace for the newly promoted Premier League side, while Troy Deeney and Connor Smith were also on the scoresheet on Wednesday.
It marked a good start to Flores' time at the helm, the Spaniard having taken over ahead of the 2015-16 season after Slavisa Jokanovic's departure.
Watford have made multiple signings in the off-season, including adding record-signing Etienne Capoue and former loan star Matej Vydra.
Ighalo struck twice in the space of four minutes during the first half, heading in just past the half-hour mark and netting a placed effort soon after.
Flores made several changes at half-time and it took until the 67th minute for Watford to go 3-0 up thanks to Deeney, who recently signed a new five-year deal.
Smith completed the scoring late on with a deflected shot from range in a solid outing for Flores' men.
Watford face AFC Wimbledon on Saturday as they continue preparations for the upcoming season, which begins with a trip to Everton on August 8.
