Valon Behrami has left Watford to join Udinese on a two-year deal.
The 32-year-old, who spent two years at Vicarage Road, completed his move back to Serie A late on Tuesday.
Udinese have the option to extend Behrami's contract for a further season.
"We closed the deal very quickly, " said Udinese director general Franco Collavino.
"Udinese wanted a player with these characteristics and with this experience in our league, Serie A, where Behrami wanted to go back to test himself."
Behrami, a Switzerland international, has previously played in Italy for Genoa, Verona, Lazio, Fiorentina and Napoli.
The midfielder joined Watford from Bundesliga side Hamburg and played 48 Premier League games for the club, but was not part of new boss Marco Silva's plans for this season.
Udinese and Watford are both owned by the Pozzo family, which has resulted in regular player transactions between the two teams.
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