Manchester City left Chelsea's Premier League title hopes in tatters with a 1-0 win at the Etihad on Saturday afternoon that was far more dominant than the final scoreline suggests.
Indeed, Thomas Tuchel must now consider the full implications of being held at arm's length by the finest team in England.
The German won three games in a row against Pep Guardiola last season, culminating in a glorious Champions League triumph in Lisbon in May.
However, after losing to City at Stamford Bridge last September, the Blues were beaten again in Manchester in worryingly one-sided fashion, with Kevin De Bruyne's sensational strike deservedly settling the top-of-the-table clash in the home side's favour.
Chelsea had gone into the game knowing that victory was imperative if they were to give themselves any hope of lifting a first Premier League title since 2017.
However, they never looked like winning. In fact, they couldn't even muster a shot on goal in the first half.
They did have one great chance after the break, but Romelu Lukaku's predictable finish was saved by Ederson.
The £97.5 million ($136m) signing from Inter recently piled more pressure on himself to justify his lofty transfer fee by conducting an unsanctioned interview with Sky Sport Italia in which he professed his love for his former club.
Although he apologised for his actions, he has left himself exposed to criticism and his recent displays haven't been enough to end the debate over his value to Tuchel's team.
He, along with the Blues' other attackers, could hardly lay a glove on Guardiola's defence.
It was hoped, remember, that Lukaku would add a whole new dimension to the Blues attack, but he has managed just eight goals in 21 appearances in all competitions this season.
Some argued that the Belgium striker was once again left isolated up front, but Tuchel, rather tellingly, did not share that view.
"Romelu Lukaku sometimes needs to do [his own] service," Tuchel said on BT Sport after the match. "He had many ball losses in very promising circumstances and he had a huge chance.
"Of course, we want to serve him, but he is part of the team, and we can do much better with our performance up front.
"We will never give up, but if City keep winning every game, nobody can catch them.”
Chelsea are still better placed than most of the chasing pack. They are also in a good position to win two trophies by the end of February (the Club World Cup and the Carabao Cup), while they remain among the favourites to win both the Champions League and FA Cup.
However, the Premier League table paints a troubling picture of the current strength of this side.
If the likes of Manchester United, Arsenal and Tottenham win their games in hand, they will close right in on the Blues, who will lose second place on Sunday afternoon if Liverpool avoid defeat at Brentford.
With many of those teams having a less busy schedule, Tuchel's side could easily get sucked into another brutal battle for a top-four finish.
When asked about whether Chelsea are looking down the table now, rather than up, Tuchel responded in prickly fashion.
"Why should we look anyway?" Tuchel added in his press conference. "If you listen carefully to what we said, the only place we look is at ourselves.
"I have no time to look at the fixtures or the tables. I don't understand the question but yes, this is part of being a top team: you are hunted. This is the Premier League."
Chelsea may be the reigning European champions, but they only scraped into the top four in each of the past three seasons and could soon find themselves in a similarly tricky position this term.
The Blues' title hopes ended at the Etihad on Saturday afternoon, but the latest dogfight for Champions League football might just be about to begin.