The Spaniard suffered a disaster in the Blues’ 2-0 defeat at Stamford Bridge to the Premier League champions.
In the first half, the 25-year-old rushed out to meet Sadio Mane, leading Andreas Christensen to drag him to the ground and get a red card on VAR review.
But it was his second-half gaffe that stole the headlines, pushing the ball straight into the forward’s path to slot into an open goal.
It has seen some question whether the man who arrived for £72m last summer will continue to be in Lampard’s plans for the season.
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Frank Lampard’s team have made wavs by signing Kai Havertz, Timo Werner, Ben Chilwell, Hakim Ziyech, Malang Sarr and Thiago Silva.
And they don’t seem keen on slowing down yet. one player who continues to be linked with the Blues is West Ham and England midfielder Declan Rice.
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But de Jong, who won the 2011/12 Premier League title with Manchester City, believes the goalkeeper sent a different message in his response to the goal-conceding gaffe.
Speaking to beIN SPORTS, the former midfielder said: “The confidence on his part right now is so low.
“You look at his body language. He doesn’t have any confidence.
“It’s doubly frustrating as a goalkeeper as you only have one position to defend – you can only blame one person.
“When you’re out, it means you’re out.
“We saw his interaction with the defenders – pointing, telling them what to do – trying to get more confidence and show his coach he can remain No.1 at Chelsea.”
De Jong’s fellow pundit Andy Gray, though, suggested Kepa may not get another chance to redeem himself to the Chelsea boss after his latest error.
The 64-year-old said: “There’s only two players over the last 15 years I can think of that haven’t suffered from a lack of confidence.
“That would be [Lionel] Messi and [Cristiano] Ronaldo – everyone else has had confidence issues.
“I think that’s where Kepa is right here, right now. I think his confidence is shot.
“I think he’s talented, I think he’s a good goalkeeper but right now he instils no confidence in any Chelsea player in front of him.
“I think Frank’s realised that and his mistake tonight has made Frank’s mind up if it hasn’t already – he needs to change his goalkeeper.”
Kepa’s poor performance was one of the five talking pointsMirror Sport picked out from Chelsea’s defeat to the Premier League champions.