Ajax, who have now lost all three European games this season, had their fate sealed in the 17th minute when captain Kenneth Taylor was sent off for a dangerous tackle and Marc Guiu, 19, scored a minute later.

Moises Caicedo made it 2-0 nine minutes later and, though Wout Weghorst reduced the deficit with a penalty, his strike was followed by spot kicks late in the first half from Chelsea's Enzo Fernandez and 18-year-old Brazilian Estevao as the Amsterdam side lost discipline.

Chelsea, who have two wins and a defeat from their three Champions League games so far, buzzed round Ajax's area for most of the second half which included an early goal from another 19-year-old Tyrique George.