Hull City confirmed earlier this week that Marco Silva had stepped down from his role at the KCOM Stadium after failing to steer the Tigers to safety in the season just finished.
Watford, meanwhile, are looking for another new manager after the club parted company with Walter Mazzarri despite the Italian ensuring a third consecutive season in the Premier League.
The 39-year-old is understood to have held talks with Porto over the possibility of a return to the Primeira Liga, but Sky Sports News reports that he has now agreed terms with Watford.
The Hornets finished 17th in the table having lost their final six games of the season and are set to make Silva their 12th manager in the space of less than nine years.
Silva won 21 points from the 51 on offer during his time at Hull, but they ultimately finished six points adrift of safety.