Chelsea fought back from 4-1 down to salvage a 4-4 draw against nine-man Ajax as a memorable night at Stamford Bridge left both sides with work to do to reach the last 16 of the Champions League.
Frank Lampard's men seemed destined for a second straight home defeat in Europe as first half own goals from Tammy Abraham and Kepa Arrizabalaga added to Quincy Promes' header and predatory finish from Donny Van der Beek to hand the Dutch champions a 4-1 lead.
However, after Cesar Azpilicueta brought Chelsea back into the game at 4-2, the visitors were reduced to nine men by second yellow cards for Daley Blind and Joel Veltman in the move that led to the hosts being awarded their second penalty of the night.
Jorginho had briefly brought Chelsea level at 1-1 from the spot in the first half and converted once more.
Reece James then levelled for the Blues and only VAR denied Chelsea a famous victory when Azpilicueta's strike was ruled out for a handball by Abraham.
Both sides are now locked on seven points at top of Group H with Valencia, who were 4-1 winners over Lille.
Chelsea had won their previous seven Premier and Champions League games with Lampard's young side earning rave reviews for their attacking intent.
The former England international hailed his side's 1-0 victory in Amsterdam two weeks ago as the best of his Chelsea tenure to date for the way they added a defensive resolve to their attacking verve.
Chelsea defensive lapses
Two weeks on, they were easily undone from crosses as Ajax went in front inside two minutes when Promes' free-kick flicked off Abraham and into his own net.
Chelsea responded immediately as Christian Pulisic's promising form of recent weeks continued with a powerful run into the box before he was brought down by Veltman.
Jorginho coolly slotted home the resulting spot-kick and Chelsea had the ball in the net again moments later but Abraham was rightly flagged offside.
Just as Chelsea were beginning to wrestle control, Ajax retook the lead with a wicked cross from Hakim Ziyech picking out Promes to head home.
Ziyech was the creator once more 10 minutes before half-time when his sensational free-kick from near the right touchline came back off the post and rebounded in off goalkeeper Arrizabalaga's face.
Chelsea started the second half strongly, but any hope of a comeback appeared to have gone when Van de Beek, who scored a number of vital goals on Ajax's run to the last four last season, rifled home another Ziyech assist.
To their credit, Chelsea never gave up even after an injury to Mason Mount threatened to compound a miserable night.
Azpilicueta sparked the fightback by prodding in at the back post after Abraham had flicked Pulisic's low cross goalwards.
Then a minute of madness turned the game on its head 20 minutes from time as Ajax had Blind and Veltman sent-off and conceded a second penalty.
Blind was shown a second yellow card for bringing down Abraham and, as the advantage was played, Veltman handled Callum Hudson-Odoi's shot inside his own box and was also booked for the second time.
Jorginho calmly sent Andre Onana the wrong way from the spot to make it 3-4.
Three minutes later, Lampard's men were level when James smashed home after Kurt Zouma's header came off the bar.
Azpilicueta thought he had completed the comeback only for his second goal of the night to be ruled out for a handball by Abraham after a VAR review.
Hudson-Odoi fired inches wide and Onana made a brilliant save to deny Michy Batshuayi a winner in a frantic finale, but Ajax held out for what in the end was a welcome point after an eight-goal thriller.
