Manchester United goalkeeper David De Gea allowed Steven Bergwijn’s near post shot through to give Tottenham a 27th minute lead in North London.
And former United right-back Gary Neville is worried by the 29-year-old’s form.
Speaking on the Gary Neville Podcast, he said: “He was the one player United could rely on for the last four years but he’s not the same.
“He hasn’t been the same for some time. When form drops for six months it’s a blip but when it goes on for a year you start to worry.
“When it goes over two years it becomes more permanent. That is now a fair representation of what De Gea is as he’s making lots of mistakes.
“Ones he would never make – he was always somebody you could completely rely on.
“It can only be a confidence thing. The arms, legs and body are the same – it’s got to be the mind.
“The reception he’s got in Spain has affected him. He’s even been booed by Spanish fans when he’s wearing the Spanish shirt.
“In the World Cup in 2018 he really struggled and from that he’s doubted himself. Mentally he’s not quite the same.”
Friday’s error is not the only high-profile mistake De Gea, 29, has made this season.