The Hornets have agreed a contract extension with Fitz Hall until the end of the season, the Watford Observer understands.
Hall re-joined the Hornets for a third time on January 6 after signing a second one-month contract, having trained with the club all season when out of contract.
The Watford Observer reported on Tuesday that the Hornets were talking to Hall's representatives but at that point a deal had not been finalised.
However, we understand a contract has since been signed which will keep Hall at the club until the summer.
Hall had a chest infection when Sannino first joined the club in December but the club gave the player a second one-month contract so the experienced defender had the chance to impress the new head coach.
The former Premier League defender was suspended for the Manchester City game on Saturday but he had started the previous two matches.
Hall excelled in his 22 outings for Watford last season but after the player initially delayed contract talks, the club’s hierarchy decided to opt for other options in the summer.
The ex-QPR, Crystal Palace and Wigan Athletic centre-back made one start and one substitute appearance after former Hornets boss Gianfranco Zola decided to re-sign the player in November following a string of injuries.
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