Tottenham shipped four goals at home to Chelsea for the second season running as Ange Postecoglou’s went down 4-3 at home after squandering a 2-0 lead.
Spurs got off to a flier when Dominic Solanke and Dejan Kulusevski capitalised on slips from Marc Cucurella to score inside 11 minutes but Jadon Sancho halved the deficit with a brilliant finish before the interval.
Two Cole Palmer penalties either side of an Enzo Fernandez strike completed the turnaround for Chelsea, but Heung-min Son scored a late consolation deep into stoppage-time.
Here are three Spurs talking points from the game...
Postecoglou has questions to answer as Spurs fade
It is now four games without a win for Tottenham since they thrashed Manchester City 4-0 at the Etihad in what appeared to be a landmark result under Postecoglou.
A fortnight later, the questions are mounting up for the head coach following another collapse, which bore similarities to their 4-1 home defeat to Chelsea last season, as well as their loss at Brighton in October.
Spurs were brilliant for most of the first half, playing with a searing intensity, but they could not maintain their levels after the break in a limp second half.
All four goals they conceded were preventable – with the penalties carelessly conceded by Yves Bissouma and Pape Matar Sarr – while Postecoglou's side were wasteful in the final third.
The difference between the first half and the way Spurs came out after the break was striking and one of the many issues for the Australian to address is whether his side can continue to play such an intense style, given the schedule and his squad’s mounting injuries.
There is no let-up for Spurs in the fixture list but the head coach is running out of options in his squad.
The mood at Spurs appears increasingly glum as the season threatens to unravel, and now they desperately need to get back to winning ways against Rangers and Southampton in the next seven days.
Missed chances cost Spurs again
The post-mortem will inevitably focus on a host of factors: Tottenham’s mentality, their injury list, their erratic defending, the officials’ decision not to punish Moises Caicedo in the first half and Enzo Maresca outwitting Postecoglou.
As much as anything else, though, this was another costly Spurs defeat that came down to wasteful finishing and poor decision-making in the final third.
Perhaps Caicedo should not have been on the pitch to win the penalty to level the game at 2-2, but then Spurs should not have allowed Chelsea to still be in the game.
Moments before Fernandez’s killer blow to make it 3-2, Son squandered a great chance to score when he raced clear and fired wide of the far post.
The South Korean was also guilty of sending a cross just behind Solanke towards the end of the first half, having earlier curled over from a good position.
Son was far from alone in being wasteful, however. Time and again in the first half, from the very first minute, Spurs turned over the ball in good positions but could not capitalise. In the end, the only goals they scored came from Cucurella's slips but they should have been out of sight by half-time.
It will not be any consolation to Postecoglou or supporters but this was another game where Spurs suggested they are capable of blowing away teams, if only they can mature and show a ruthless edge in the final third.
Increasingly, though, the question is whether those glimpses of promise are enough.
Romero and Van de Ven returns appear to backfire
The unexpected returns of both Romero and Van de Ven from injury provided Spurs with a huge pre-match boost but neither centre-half managed to finish the match, raising serious questions about their readiness to start.
After just 14 minutes, Romero went down after a seemingly innocuous flick and was replaced by Radu Dragusin.
The Argentine looked in considerable distress as he left the field but he did return to the bench before half-time, without any obvious strapping on his legs.
Van de Ven lasted until the 79th minute when he went needing treatment. It looked like cramp, but Spurs will now face an anxious wait to discover if he has suffered a recurrence of his recent hamstring injury, as well as the extent of Romero’s complaint.
Johnson was also forced off early in the second half with what looked like a muscle injury, going down after sprinting forward on the counter.
With Richarlison, Wilson Odobert and Mikey Moore not expected to return to the new year, an injury to the Wales winger would be an enormous blow for Spurs.
Bissouma, meanwhile, will be suspended against Southampton next week after picking up a fifth yellow card of the season.
It never rains, it pours.
