Rene Gilmartin has re-joined Watford two years after leaving the club.
The 27-year-old goalkeeper has signed a one-year contract at Vicarage Road and leaves Irish club St Patrick's.
He first joined the Hornets from Walsall in 2010, but struggled to embed himself in the first team, making 10 appearances in two seasons.
Gilmartin, who has one Under-21 cap with the Republic of Ireland to his name, has also played for Crawley Town, Plymouth Argyle and Yeovil Town in the Football League.