Gianfranco Zola has resigned as Watford head coach.
The Italian ends his time in charge of the Hornets after 17 months at the helm.
Watford confirmed that they had accepted the 47-year-old's resignation with "great sadness" on Monday afternoon.
In an open letter released via the club's website, Zola said: "I must place Watford Football Club first in my thoughts and it is for this reason that I have taken my action.
"I feel that it is in the best interests of the team that somebody new is given the chance to bring the success which we have all hoped for and worked very hard for.
"It is for a variety of reasons, and not just over one matter or one moment, that I feel this is the right decision for me, in the best interests of the club - and I know I can trust you, the supporters, to respect my decision fully."
Zola led Watford to the Championship playoff final last season where they were denied a place in the Premier League by Crystal Palace.
"Last season was such an amazing time, for the players, the staff and the supporters. And I loved that journey. Every minute of it brought a new challenge, different experiences and a lot of learning," he added.
This season Watford began as one of the leading pack but have gone nine games without a win in the league to drop to 13th in the table.