Quique Sanchez Flores says Watford will remain in his heart forever after becoming the second manager sacked by the struggling club this season.
Sanchez Flores' second spell in charge of the Premier League's bottom side lasted just 85 days and came to an end following Saturday's 2-1 loss at Southampton.
Watford expect an "imminent" appointment of a new head coach, with former Brighton boss Chris Hughton the heavy favourite.
Sanchez Flores expressed gratitude and offered encouraging words to the club and its supporters following his dismissal.
"I would love to say a big thank you from my heart for the appreciation, respect and support that I've felt in each moment I've lived in the lovely family that Watford FC is," he said in an open letter on the club website.
"This is not the time to think about individual feelings, it's time to have a collective reaction.
"I wish you all the best. Stay strong. You'll always be in my heart."
Spaniard Sanchez Flores, who initially managed at Vicarage Road during the 2015-16 campaign, had been reappointed on September 7 following the dismissal of compatriot Javi Gracia.
He failed to spark an upturn in results and managed a solitary victory from his 10 league games in charge, which included an 8-0 thrashing at Manchester City.
The Hornets had been on course for a precious three points at fellow strugglers Southampton before conceding two late goals which left them rooted to the foot of the table.
Sanchez Flores said after the defeat at St Mary's that his players were suffering with nerves and admitted he did not know whether he would retain his job.
The 54-year-old's fate was announced on Sunday morning, with Watford chief executive Scott Duxbury saying results had "dictated" another change of management.
The south-coast defeat, which followed a 3-0 home loss to Burnley, left the Hornets six points from safety ahead of Wednesday's trip to high-flying Leicester, by which time they are likely to have their third permanent manager of the season in the dugout.
"Quique is a man of great integrity and it was clear how much he wanted to have a positive impact, but ultimately results have dictated our decision," Duxbury said in a statement.
"The appointment of a new head coach is imminent and, with nearly two-thirds of the season remaining, we will provide all the support necessary to make the coming months successful."
Sanchez Flores became the third Premier League manager to be sacked in less than two weeks following the departures of Mauricio Pochettino at Tottenham and Unai Emery at Arsenal.
The current frontrunner for the vacancy is Hughton, who has been out of work since being sacked by Brighton in May and has also managed Newcastle, Birmingham and Norwich.
The 60-year-old has reportedly turned down advances from a number of Sky Bet Championship clubs since leaving Albion as he would prefer to return to the Premier League.
Sam Allardyce, Paul Clement and former Real Betis boss Quique Setien have also been linked with the position.