Watford have signed Portuguese forward Vivaldo Semedo on a five-year deal for an undisclosed fee from Serie A side Udinese.
The 20-year-old spent last season on loan at Portuguese second division side Vizela, where he scored nine times in 25 appearances.
"Vivaldo is exactly the kind of player profile we want and need at Watford," sporting director Gian Luca Nani told the club website.
"He will learn under [head coach] Paulo [Pezzolano] and we know he will adapt quickly to English football because we have already seen the development over a short period of time.