Watford have signed midfielders Matheus Martins and Leandro Bacuna.
Curacao international Bacuna, 31, has signed until the end of the season after leaving Cardiff City in July.
Brazilian Martins, 19, was linked with a move from Fluminense to Udinese, the Italian side that the Hornets' owners - the Pozzo family - also control.
A loan move to Watford had been expected but when contacted, the club would not confirm the terms of Martins' arrival or who he has joined from.
Fluminense confirmed Martins' departure but did not state the name of the club the Brazil Under-20 international had joined.