The Chelsea manager left his squad in little doubt about his displeasure after an abject display saw them squander an opportunity to make ground in the Premier League title race.
Chelsea have an immediate chance to atone for a disjointed performance — which Mourinho described as lacking in all departments — when they host German side Schalke in the Champions League this week.
Several of the players who failed to impress at St James’ Park are unlikely to have an opportunity to restore their reputations immediately, with Mourinho ready to shake things up to avoid a repeat of the 90-minute no-show in the northeast.
Taking his own share of the blame for a defeat that leaves Chelsea with just five points from five away league games so far this term, the Portuguese said: “I made 11 mistakes with my team selection — 11 mistakes.
“That’s the feeling I have when my team plays so badly. We deserved to lose because for 45 minutes we played at the level of a friendly. The result is down to the fact that one team wasn’t there.
“There was no aggression there and we lacked intensity. It was a bad performance and it sends me home with a lot to think about because I have to try and understand where a display like this came from. I have to admit I’d be worried if we play like that again.”
Mourinho concedes Chelsea’s patchy away form is a concern after they succumbed to second-half goals from French duo Yoan Gouffran and Loic Remy.
“We’ve won just once away in the league this season and that worries me,” he said.
“You have to come here to Newcastle with a certain mentality, and we just didn’t show that. We were lacking everything, to be honest, and that’s how I explain a result like this.
“We’re 10 games in and it’s an open title race, but that’s not something I’m thinking about every week at the moment. I must go home and reflect on this game because Newcastle gave us a lot of space to play in and hurt them, but we just lacked any kind of sharpness.”
Newcastle ended a testing week on a high with a fully deserved win to help erase the memory of their derby defeat at Sunderland last weekend.
Manager Alan Pardew paid tribute to his side and dedicated the win to owner Mike Ashley, who has come in for criticism for banning three local newspapers from reporting on Newcastle’s games in a stand-off over their coverage of the club.
“We started off conservatively, because if you go chasing from the start you’re in for a long afternoon against Chelsea,” he said.
“In the second half we had a bit more energy to put more pressure on them and that cranked up as we went on.
“We’ve been playing well for the past four or five games, and if you work hard enough and keep showing that spirit you’ll get the breaks, and that happened today (Saturday). Our players really put in a shift and got their reward.
“This win is for Mike Ashley and all our Newcastle fans. Trust me, he is a fan. I’m pleased for the club. We’ve had to make a stand with the local press. We want them to be onside with us and this was about giving a message to our fans that we are very much alive and kicking.”