Former Atletico Madrid manager Quique Sanchez Flores has been named as Watford's fifth boss in a year.
The 50-year-old's appointment on a two-year deal comes after talks ended with Slavisa Jokanovic, who led Watford to promotion to the Premier League.
Jokanovic's contract ends this month and it is believed Watford were unwilling to meet the £2.5m basic salary the 46-year-old asked for.
Watford instead offered £1m and a further £1m based on performance.
Former Real Madrid, Valencia and Spain right-back Flores took charge of Getafe in January, but quit after only 11 games, citing personal reasons.
Flores's managerial achievements include winning the Europa League and Uefa Super Cup in 2010 with Atletico, and the Portuguese League Cup with Benfica in 2009.
|Watford's five managers in a year|
|Manager||Win percentage||Days in charge|
|Quique Sanchez Flores||N/A||N/A|
He takes over from former Chelsea midfielder Jokanovic, who was appointed at Vicarage Road in October, replacing Billy McKinlay after the Scot had just eight days in charge.
The Hornets had started the 2014-15 campaign with Beppe Sannino as the manager, but he was replaced in September by Oscar Garcia, who quit later that month because of health concerns.
Watford won 21 of their 36 games under Serb Jokanovic, and they ended an eight-year absence from the top flight by finishing second in the Championship, missing out on the title to Bournemouth thanks to a last-minute Sheffield Wednesday equaliser on the final day of the season at Vicarage Road.
The Hornets said in a statement: "Watford FC would like to take this opportunity to thank former head coach Slavisa Jokanovic, along with assistants Ruben Martinez and Javier Pereira, for an outstanding contribution to the success of the club."