Nobody enjoys seeing a decent man walking the plank, but for Graham Potter this might be the tipping point.
As Oliver Skipp and Harry Kane bagged only Tottenham's eighth win in 62 Premier League meetings with Chelsea, the Blues head coach looked a broken man. In a ruthless business where winning is the only currency that matters, Chelsea's wretched form – one win in 11 games in 2023, and just six goals in 12 Premier League games – comes with a three-digit warning code: P45.
Fire and brimstone are welcome ingredients at any derby, but Potter's side brought only synthetic bravado to the party. Owner Todd Boehly's loyalty to his head coach has been a refreshing change from the knee-jerk tendency, but as scientist Albert Einstein warned: Insanity is doing the same thing over and over again and expecting different results.
And for the first time, Potter admitted afterwards that he cannot rely on his paymasters' indulgence to last forever if results don't improve.
Chelsea are now closer to the bottom three than the top four. How did that happen after spending £600 million in two transfer windows?
Yes, they still have the remaining carrot of next week's Champions League second leg against Borussia Dortmund, but right now that looks like a mirage in the desert.
Tottenham we can deal with in short measure: They have now won all four games when head coach Antonio Conte has not been confined to sick bay or the naughty step. But Chelsea barely created a chance worthy of the name.
They had already survived Pierre-Emile Hojbjerg's deflected shot against the foot of a post when they were lucky to emerge from an outbreak of pat-a-cake nonsense in first-half added time with 11 men. After referee Stuart Attwell sent off Hakim Ziyech for catching Emerson Royal in the face during a melee of posturing, immediately he ran to the pitchside monitor to review his own decision on the advice of VAR Paul Tierney.
Replays showed Ziyech had shoved the Spurs defender on the shoulder, but the follow-through deflected into the Brazilian's right jaw, and Attwell reduced red card to yellow.
Even if it was the right decision, what a mess. Attwell is no stranger to bizarre decisions – he awarded Reading their notorious 'ghost' goal at Watford 15 years ago – and now he's gone from ghost goals to phantom red cards.
Ziyech, who was virtually in the tunnel before he was called back, can consider himself lucky, but the Premier League ministry of truth issued a statement explaining that “the red card was downgraded as it did not meet the threshold for violent conduct.”
In truth, the bust-up made Conte and Thomas Tuchel's spat of Queensberry Rules on the touchline at Stamford Bridge six months ago look like the Rumble in the Jungle. But if the Italian - convalescing in Italy after his gallbladder surgery - was crying out for some football, at least he only had to wait until 20 seconds after the break for the get-well-soon card to arrive.
Kepa Arrizabalaga should have done better than shovelling Royal's shot away as if he was putting the cat out, and when Skipp picked up Enzo Fernandez's clearance, 25 yards out, his thrilling shot kissed the bar on its way beyond the startled Chelsea keeper. In truth, Kepa should have done better with Skipp's soaring drive, but only the stoniest heart would have denied the home-grown Tottenham youngster his first goal in 67 appearances for the club.
Chelsea went through the motions of a fightback but rarely threatened an equaliser until Potter's goose was cooked eight minutes from time. Sub Heung-min Son's corner was flicked on by Eric Dier and Kane administered the last rites from close range, his 20th goal of the season.
Potter responded by bringing outcast Pierre-Emerick Aubameyang off the bench but it was a token gesture, far too late to retrieve a lost cause. Long before the end, he was being serenaded by the chorus of the doomed, You're Getting Sacked In The Morning.
And for all his owners' past assurances, insipid defeat on a ground where Chelsea had a 100 per cent record may be the day Potter's credit ran out.