Gary Neville has urged caution over the prospect of Dean Henderson becoming first-choice goalkeeper at Manchester United next season, despite David de Gea's indifferent form.
De Gea was again in the spotlight when his failure to stop Steven Bergwijn's shot allowed Tottenham to take the lead against United last Friday, though the Red Devils hit back to secure a draw from the game.
The Spain international overcame a shaky start at Old Trafford to become a cornerstone in the team during a period of transition, yet a slip in standards has raised questions over whether he should remain as number one.
Yet while Henderson has impressed in the Premier League during a loan spell at Sheffield United this season, former United defender Neville is wary of pushing the 23-year-old into the top job at Old Trafford too soon.
"David de Gea, for three or four years, was probably the best goalkeeper in the world - certainly the best in the Premier League," Neville said on Sky Sports.
"He was player of the year here and, in a very difficult period for Manchester United post Alex Ferguson, was a shining light. The only player really you would say could go into any other team in the Premier League, or the world.
"Since that 2018 World Cup, though, he's had a real difficult time.
"What I don't buy into is that Dean Henderson at Sheffield United, obviously from Manchester United on loan, can go into that goal in front of the Stretford End and adapt to what the demands are of being a Manchester United goalkeeper.
"It takes a special character to play in that goal. What I think David de Gea has done in the four or five year period before this last 18 months is build up a lot of credit, whereby he actually deserves a break, the idea he is given the opportunity to correct his form and get it back to where it needs to be.
"When a goalkeeper, or any player, goes through a rough patch it's mentally tough. He's at one of the biggest clubs in the world and the scrutiny is on him constantly.
"There is no escape at this club – and that is why I'd be a little bit cautious around Dean Henderson. That is a lonely old place out there to make a mistake if you're a Manchester United goalkeeper. With respect to Sheffield United, it's very different making a mistake for Sheffield United."
He continued: "To make that decision, which is a huge call, to say that Dean Henderson comes back to Old Trafford and is the number one, you're essentially dismissing David de Gea and what he's done for the club over the past seven or eight years.
"I would just urge caution on that, at this moment in time."
Neville played with Peter Schmeichel and Edwin van der Sar during his own career, yet also saw up close how tough it can be as a goalkeeper at United.
"I've seen it before with players during my period at the club," the ex-England defender said. "We had two great goalkeepers during my time – Peter Schmeichel at the beginning and Edwin van der Sar at the end.
"In between that, there were real challenges with goalkeepers.
"At times there were young goalkeepers who were talented but found it very difficult to cope with the scrutiny, plus the levels of concentration that are required."