The Young Boys substitute had even turned to celebrate, before realising De Gea had somehow stopped it.

The United boss is confident the Spaniard will sign a new deal, with his current contract up in 2020 once the one-year extension clause is activated.

"He is a world-class player," Mourinho said. "He is the best goalkeeper in the world and, if our ambitions are to be a big club, to be a winning club, you need the best goalkeeper in the world – and you need also some other players the best in the world.

"In this case, we have the best goalkeeper in the world and I know that he wants to stay.

"I know that his agent is happy to do what the player wants and I also know that the board wants him to stay and they're working on that, so hopefully sooner or later they arrive into good conclusions."

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