During his career, Mr Keegan played for several clubs across Europe.
It only took nine minutes for Viktor Gyokeres to put the Gunners ahead.
The Blues’ poor run also included defeats to Paris Saint-Germain in the Champions League.
Antoine Semenyo opened the scoring for the hosts in the 24th minute.
Cunha doubled the lead for United in the 56th minute when he fired a pass from Casemiro into the roof of the net from close range.
In the 70th minute, Cucurella equalised for Chelsea when he lunged to nod home a loose ball inside the West Ham 18-yard box.
Chelle emphasised that his squad practised penalties at every training session during the tournament.
The 29-year-old player attributed the progress to the brotherhood bond the players had established.
Reduced to ten men, the Blues were immediately put under pressure and United capitalised.
Champions Liverpool face Bournemouth in the season’s opening match as league organisers release the matchday schedules for the upcoming season.
