Jose Mourinho calls Chelsea's opening half at Newcastle their worst under him
The Portuguese gave his team a "minus one out of 10" rating for their first 45 minutes at St James' Park and blamed individual errors for gifting the Magpies 2-0 lead.
Asked if that was as badly as the Blues had played under him, Mourinho said: "Yes, for sure.
"I have played so many matches with Chelsea over seven years and we have had some bad performances. I remember one at Middlesbrough in 2005, 2006, something like that, we were losing at half-time 3-0, so we have had a few.
"But this first half, I can rate as one of those performances, yes. I put it down to awful individual performances. When you have so many bad individual performances, it's impossible for a team to be a team."
Newcastle forced their way ahead - and deservedly so - three minutes before the break when Ayoze Perez took advantage of indecisive defending to volley home from Vurnon Anita's cross, and when Georginio Wijnaldum headed home Perez's 60th-minure corner, a fourth successive home win over the Blues looked to be on the cards.
However, Mourinho quickly shuffled his pack and two of his substitutes did the trick when Ramires reduced the deficit with a 79th-minute piledriver and Willian levelled direct from a free-kick with just four minutes remaining.
The Chelsea boss is yet to win a league game on Tyneside and had lost on his previous three visits, and that led him to question Newcastle's mentality.
He said: "I think maybe one of the reasons why Newcastle over the years doesn't get good positions is because of this mentality, it's because they choose some matches to sweat blood and in other matches, they don't.
"This is an attitude typical of a team that wins nothing. It's bad for them because if they play like this, they win many matches at home, and they don't. But this is their problem.
"The reality is that they fought hard, they gave everything, they followed a line that many pundits gave straight away - you have to fight, you have to kick, you have to tackle, you have to run, so they were exactly that, and they fought for a point, and I think they deserved a point the way they fought."
Willian's late equaliser denied Magpies head coach Steve McClaren a first league win, but he was able to take positives from a vastly-improved display in which summer signing Aleksandar Mitrovic played a significant role on his return from suspension.
McClaren said: "It's difficult to know what to think after that, and then you have got to try to come back down and put it into some kind of perspective, and that's what we must do, put it in perspective in terms of performance, in terms of reaction and in terms of what we have got.
"What you got was a collective togetherness, which we talked about a lot, and that wasn't just the players and the dressing room and the staff, that was the supporters because after this week, the supporters could have just waited and seen what was going to happen.
"But they didn't, they responded from the first whistle and that's what's unique about this football club, this set of fans, and the players responded and gave a performance which was more like what we want - attitude, character, organised, really disciplined and courage to play, and we played some good football.
"In the end, we could have won it; in the end, we could have lost it. With five or six minutes to go, the momentum had swung and to hang on in there.
"Yes, it was a good display, but that's the benchmark now, that's the standard."