The Spaniard had a €4m release clause in his contract which Stoke were more than willing to pay to secure the former Atletico Madrid and Valencia boss ahead of second choice Martin O’Neill, who must now return to Dublin to negotiate a new deal with the Republic of Ireland.
Stoke were keen to find a coach with Premier League experience after their dismissal of Mark Hughes, and were impressed with Sanchez Flores’ performance during his one season with Watford.
The Hornets made the ill-advised decision to replace the former Spain defender with Walter Mazzarri despite Sanchez Flores keeping the Vicarage Road club in the Premier League at the first time of asking and reaching the FA Cup semi-finals.
Sanchez Flores is expected to fly to England this weekend and complete the formalities that will see his salary vastly increase even before performance-related bonuses, while Stoke have had a delegation in Barcelona for the last few days in order to convince him to take the post.
They had hoped to announce the hire on Friday but negotiations dragged on, meaning he is likely to watch Monday night's game with Manchester United from the stands rather than the touchline.
Espanyol are already lining up former Malaga manager Javi Gracia to replace the 52 year-old, with sources at the club admitting that a change of head coach is imminent.