Charlton have confirmed the appointment of Jose Riga as head coach following the sacking of Chris Powell.
Thibaut Courtois' father has denied reports that his son will join Real Madrid once his contract with Chelsea expires in 2016.
The Spanish club, also owned by Watford supremos the Pozzo family, confirmed on their website that Iriney has agreed a season-long deal at Vicarage Road.
The 32-year-old has spent more than 10 years in Spain and also played for Rayo Vallecano, Celta Vigo, Real Betis and Almeria.
Watford caused controversy last season by bringing in a host of loanees from Granada and the other Pozzo-owned club, Udinese.