Former Chelsea midfielder John Obi Mikel labelled Nicolas Jackson’s sending-off against Flamengo a “stupid mistake” and said his old club lack leaders.

Jackson was shown a straight red card for a studs-up challenge on Ayrton Lucas four minutes after coming on as a substitute for new signing Liam Delap at the Lincoln Financial Field in Philadelphia as Chelsea collapsed to a 3-1 loss at the Club World Cup.

Chelsea looked to be on track for a second win at the competition after Pedro Neto’s breakaway opener in the first half but poor defending saw them concede twice in three minutes after the break, with Jackson’s moment of madness following moments later.

Wallace Yan’s late goal sealed the victory for Flamengo but Jackson’s sending-off, on his 24th birthday, and only six weeks after he saw red for an elbow on Newcastle defender Sven Botman in the Premier League, was the dominant talking point.

Speaking on DAZN, Mikel, who won 11 trophies in an 11-year spell at Chelsea, said of Jackson’s red card: “Unbelievable. Stupid, stupid, stupid mistake.

“I don’t know what’s going through his head. You come into the game, you’re 2-1 down, your team needs you, and you do that.

“He did it in the important Premier League game against Newcastle, when we needed to win to qualify for the Champions League places, and he has done it again.

“You can’t keep making mistakes.”

Jackson’s red card came after an impressive first start from Delap, a £30m signing from Ipswich who has joined Chelsea to compete for the Senegal international’s starting spot in Enzo Maresca’s team.

“I don’t care what his frustration is,” added Mikel. “Chelsea is a massive football club and it’s about competition.

“If you are angry, if you are p****d off that Delap is coming to the club and he is going to be your competition, you have to embrace it.

“If you are a big player, you embrace it.

“Jackson needs to have a look at himself and think where he wants his Chelsea career to go from here.

“The manager has brought in a striker, so now if the manager starts to doubt him, if he keeps making mistakes and letting his team-mates and the club down, then it is time for Delap to start the games.

“The manager has a decision to make now.”

Maresca wouldn’t be drawn on Jackson’s sending-off in his post-match interview. “It was a red card, so nothing to say,” he said.

But Chelsea defender Marc Cucurella defended his team-mate, saying he will learn from it. “It is a bit of bad luck,” said Cucurella.

“He tried to put his foot in to kick the ball but he kicked the player’s leg. That’s it. We now miss him for the next game.

“He is a young player with a lot of quality and maybe he needs to improve this. We are not perfect, it’s part of the game.”

Jackson apologies for dismissal

Jackson himself apologised after his costly sending-off on Instagram, writing: “I want to say sorry. To the club, the staff, my teammates, and all the fans watching, I let you down.

“Another red card… And honestly, I’m so angry at myself. I work hard every day to help the team not to put us in this kind of situation.

“I still don’t fully understand how it happened. But one thing is clear: it wasn’t intentional. Just a moment in football that went the wrong way.

“No excuses. I take full responsibility. I’ll reflect, I’ll grow, and I’ll come back stronger for the badge and for everyone who believes in me.

“Sorry. Sorry, Sorry.”

‘Chelsea need to bring in a top goalkeeper’

Mikel’s criticism was not just aimed at Jackson. He felt Chelsea’s collapse was indicative of a lack of leadership generally.

“When you talk about leaders, people that can be on the pitch and control the game and their team-mates, that is what Chelsea had when the likes of John Terry and Didier Drogba were at the club.

“People who can call the players around and say, ‘Listen, let’s calm down a bit’. I don’t see that here, I don’t see leaders. I just see players making mistakes.”

Mikel felt goalkeeper Robert Sanchez was one of those players, in addition to Jackson.

“I’ve talked about him so many times,” he added. “Sanchez, I don’t think he is a goalkeeper that can lead us to winning titles.

“If you want to win titles and become a big football club, you need to have a top goalkeeper.

“For me, I’ve said it so many times, he’s not that guy, he’s not that goalkeeper.

“We need to strengthen this summer and bring in a top, top goalkeeper if we want to compete in terms of winning titles.”

The defeat to Flamengo leaves Chelsea second in Group D at the Club World Cup, three points behind leaders Flamengo ahead of their final group game against ES Tunis on Wednesday.