It was a fightback befitting of the champions as Jose Mourinho's side came from two goals down to secure a draw, but it was not a performance that suggests Chelsea will hold on to their crown. Mourinho knows as much and it annoys him.
The problem is, he cannot understand why his team has lost its cut and thrust. He cannot fathom why they have also forgotten how to do the basics in defence properly.
Although their fans sang "that's why we're champions" to goad Newcastle United's home support after their two-goal lead had vanished late in the second half, they will also know champions have to be better than this.
Perhaps the biggest insult that can be used, in light of Mourinho's intense hostility towards Arsene Wenger, is that this Chelsea team looked like Arsenal on a bad day.
They dominated possession, but rarely did anything with it. They created chances and failed to take them. They passed the ball sideways and backwards, but not forwards often enough to stretch Newcastle's deep defence.
"I try to read the game but do not understand why we were so poor," said Mourinho, whose side are eight points adrift of the new league leaders Manchester United.
"It is easy for me to analyse the moments in a game and everything that makes a football game.
"That is completely clear for me, but the reason why we did that, or more accurately why we didn't do what the team was supposed to do, that is where there is a question mark."
Having fallen behind just before half-time when Kurt Zouma misjudged a cross and Branislav Ivanovic failed to prevent Ayoze Perez beautifully controlling the ball, before swivelling to smash it in via the inside of the post, Chelsea were dominant after the break.
They had pinned Newcastle in their own half, but managed to concede a second goal when Cesc Fabregas allowed Gini Wijnaldum to get away from him at a corner and glance a header beyond Asmir Begovic.
Newcastle, though, were too cautious as they understandably tried to cling on to what would have been their first league win of the season. With two strikers in Perez and the combative Aleksandar Mitrovic, this was a Newcastle side far easier to roar on - as their supporters did.
But they invited pressure in the second half by dropping everyone other than Mitrovic behind the ball. It allowed Chelsea to build up a head of steam and eventually the pressure broke McClaren's men.
Ramires's goal was a pearl, a stunning shot into the top corner from outside the area.
The second came from Willian, when the goalkeeper Tim Krul was distracted by the run of Ramires and allowed the Brazilian's free-kick to sneak inside the far post.
Chelsea should have scored three. Pedro was sent in on goal, but a woeful finish ended up in the stands. That was before Willian had equalised and the visitors had another chance to grab the three points when Ramires headed straight at Krul.
That would have been extremely harsh on Newcastle. McClaren has inherited a team full of players who save their best performances for the big games. But this was much better from the Magpies. They were, just as they had been against Manchester United and Arsenal earlier this season, full of energy and determination. When it was put to him that Newcastle did not play like this in less glamorous fixtures, McClaren replied: "I will be levelling the same [accusation] at the players.
"It is exactly right. We did it at Old Trafford, Arsenal and now Chelsea. They have performances like that in them.
"If we had just won, it would have been an absolute high.
"But we have still shown something important. We have seen that already, then it goes, then it comes back. It needs to be consistent and that is what we are looking for now."