Dermot, who was 56, was a popular figure at both Stamford Bridge and Cobham during his time with Chelsea between 2007 and 2014.

Head of youth development Neil Bath worked with him throughout that time. He said: ‘There are no words to convey the sense of shock and loss we all feel at this news.

‘Dermot was a good friend to many of us here at the Academy, including myself. His love and passion for football were infectious, and we will all miss him greatly.’

A youth team player at Arsenal, Dermot also appeared for Blackpool at the beginning of a career spent largely in non-league. He returned to the Gunners as a coach in 1999, helping develop a string of future first-team players, including Cesc Fabregas, before joining Chelsea in 2007.

Following Brendan Rodgers’ departure and Paul Clement’s promotion to the reserve team, Dermot took control of the youth team, and led Chelsea to our first FA Youth Cup success in 49 years in 2010.

He was appointed reserve team manager in 2011 as Steve Holland joined the first-team coaching setup, and, following the competition’s reorganisation to an Under-21 format, the Blues were crowned national champions in 2014 thanks to a 2-1 win over Manchester United at Old Trafford. Our goalscorers on the day were Charly Musonda and Lewis Baker, in a team also featuring Andreas Christensen, Ruben Loftus-Cheek and Nathan Ake.

Following a brief spell as international head coach of the Chelsea Foundation, Dermot was appointed manager of Crawley Town in April 2016, leaving his position in May this year.

The thoughts of everybody at Chelsea are with Dermot’s family and friends at this sad time.