Watford started the season with consecutive wins after beating Burnley 3-1 for their first away victory of the year.
Andre Gray scored Watford's first away goal since 2 January after just three minutes when he exchanged passes with Troy Deeney and fired beyond Joe Hart.
Burnley were level three minutes later when James Tarkowski headed in a Johann Berg Gudmundsson corner for his first Premier League goal.
But Watford went back in front on 48 minutes through Deeney, who received a sublime pass from Abdoulaye Doucoure to slot in.
Three minutes later, Hughes netted a ferocious drive as the Hornets joined Manchester City, Chelsea, Tottenham Hotspur and AFC Bournemouth on six points.
See: Burnley report | Watford report
Next fixtures
Burnley: 26 Aug v Fulham (A)
Watford: 26 Aug v Palace (H)
