Ajax retook the lead when Promes headed in a brilliant cross from Hakim Ziyech, whose free-kick from a tight angle led to the third goal as the ball came back off the post and went in after hitting home keeper Kepa Arrizabalaga in the face.
Once Azpilicueta’s close-range tap-in made it 4-2 and opened the door, Chelsea barged through it as Ajax found themselves pinned back and suffering a numerical disadvantage.
Watch All GOALS and Highlights: Chelsea 4-4 Ajax
Chelsea mounted a stirring fightback from 4-1 down to earn a crucial Champions League point as Ajax ended with nine men on a night of high drama at Stamford Bridge.
Chelsea boss Frank Lampard told BT Sport: “I can’t explain the game. For all the things we might analyse back, the madness of the game, we are here for entertainment I suppose and anyone who watched that has to say ‘what a game of football’. Respect to Ajax, what a spectacle.