Newcastle's injury crisis meant they named three goalkeepers on a hugely inexperienced bench for Saturday's visit of Chelsea, but they brushed the Blues aside.

Pochettino's side came into the game on the back of impressive results against Tottenham and Manchester City but lost Reece James to a red card and saw Thiago Silva hand Newcastle a goal amid an ill-disciplined display.

• Newcastle 4-1 Chelsea - Report and highlights
• Watch free Premier League highlights
• Live Premier League table | Get Sky Sports
• Stream the Premier League with NOW

Asked about Silva's uncharacteristic error, Pochettino pinned the blame on his team as a whole, saying: "It's a bad mistake but I am talking more about energy.

"We did not prepare ourselves to compete in the best way. This is my concern. We thought we were ready to compete but we didn't compete in the way the competition demanded.

"Even if Newcastle weren't great, it was an easy win. It was so easy with the way we conceded, and we were so soft in every challenge.

"We didn't show that we were playing for something important. That's what makes me angry and disappointed. Even if we are a young team and need to learn, these types of games make me very angry."

Pochettino suggested his young side had taken their eye off the ball after their impressive recent results, adding: "It's about showing more personality and character. We are young but cannot miss this type of opportunity.

"After Tottenham and Manchester City, people praise Chelsea, but then, 'OK, I stop one step before. I didn't do the effort in the right moment - it's OK, my team-mate is going to fix it'. That is the problem.

"We need to show more strength in our mental game. We need to blame ourselves. We need to be more focused.

"We conceded easy goals. It was our worst game of the season."

Merson: Chelsea didn't match Newcastle's effort

Newcastle may have been missing a host of senior players but they "overwhelmed" Chelsea, according to Paul Merson.

Speaking on Soccer Saturday, he said: "I said before the game that if Chelsea could stay in the game for 30 minutes, they had every chance of winning. But second half, Newcastle worked their socks off.

"They've got good players but they work their socks off. That is what they do. They overpowered Chelsea and ran them ragged at the end.

"They've [Chelsea] got to work hard. They've got to get back to the drawing board. It's two steps forward, three steps back.

"I don't think it's that they're not fit. I think their confidence is low and they got overwhelmed today and overpowered.

"They saw that a lot of Newcastle's stars weren't playing and they didn't match their work rate."

Chelsea finished the game with an expected goals total of just 0.58 - which was dwarfed by Newcastle's 2.28 - and Nicolas Jackson failed to register a shot.

Merson was left unimpressed with the No 9's impact, saying: "I'm not blaming Jackson but Chelsea need a striker.

"If they don't get a striker, they are going to struggle. So many times they broke today and the threat wasn't there.

"He's a young kid but if they had another centre-forward there, he would have been brought out of the team for a little rest and to learn the game.

"If they don't get a centre-forward, they are going to be nowhere near getting into the top four. And I'm not talking about this season - I'm talking about next season as well."

Analysis: Chelsea's leaders go missing

Sky Sports' Joe Shread:

Pochettino must be becoming increasingly frustrated at the fragility of his Chelsea side. After going toe-to-toe with champions City in their last outing, the Blues were a mess at Newcastle.

Surrendering their hard-earned momentum is becoming a worrying theme for this youthful Chelsea team. After successive Premier League wins at the start of October, they threw away a two-goal lead at home to Arsenal, before following that up with defeat at home to Brentford.

And back in September, Pochettino's team backed up his first win as Blues boss with a three-game run that featured one point and zero goals.

Inconsistency is to be expected after Chelsea's dramatic pivot towards youth, but that decision only highlights the need for their more experienced players to lead by example.

That did not happen at St James' Park. James was the main offender thanks to his dismissal, while Silva's mistake killed the game.

Even Raheem Sterling must take some responsibility, with the winger giving away a needless free-kick and then compounding his error by collecting a booking for dissent in the build up to Jamaal Lascelles' winning goal.

Conceding three goals and a red card in 23 second-half minutes, Chelsea’s leaders abandoned their post at St James' Park. Once again, it's back to the drawing board for Pochettino and his side.