Watford have signed Sporting Lisbon defender Marvin Zeegelaar on a four-year deal for £2.75m.
The 27-year-old, who started his career at Ajax, made 37 appearances for the Portuguese side last season, including five in the Champions League.
The Dutch left-back joined Sporting in 2016 from Rio Ave, having previously had a loan spell at Blackpool in 2013.
Watford have also signed defender Molla Wague and goalkeeper Orestis Karnezis on season-long loans from Udinese.
Karnezis, 32, has won 42 international caps while 26-year-old Wague has four goals in 25 games for Mali.
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