Losing David de Gea would come as a huge blow to Manchester United, yet Jose Mourinho is reportedly willing to let him leave if he so pleases.

According to Spanish outlet Marca, per the Mirror, the Portuguese has made clear to his players that he will not make anyone stay against their will.

It's Real Madrid who are once again looking to make a move for De Gea, who was linked with a move to the Bernabeu in the 2015 and 2016 summer transfer windows.

For various reasons, including a paperwork mix-up, the Spain goalkeeper ended up staying put.

All signs now point towards a summer departure. In addition to Marca's claims, not to mention comments made by De Gea in February, he's put his £3.85 million mansion up for sale.

In response to a question about joining Real, De Gea said: "Nobody knows the future. The future is the future. I'm very happy at United, it's a great club.

"I'm enjoying my football in England. I will not talk about that. On that subject I will not talk any more. Now I must stay focused with my club."

Instead of quelling rumours of a summer move to the Spanish capital, De Gea fuelled them by insisting anything can happen in the future.

Mourinho will inevitably be preparing for the worst by lining up potential replacements - and it would see he's found one.

According to Manchester Evening News, Jan Oblak's agent was in Manchester earlier this week to discuss a summer transfer to Old Trafford.

The Atletico Madrid star has a mammoth release clause of £85 million, but Mourinho won't hesitate to splash the cash if he loses a world-class goalkeeper in De Gea.

A source close to Oblak told MEN recently how playing for United would be an "honour", and that anything could happen if De Gea does join Real.

"I think for every player it is an honour to come to the UK and play for clubs like this one," they said. "If De Gea goes back to Spain, everything is possible."

AC Milan's Gianluigi Donnarumma is another on Mourinho's radar, though the 18-year-old would likely cost even more than Oblak.

What's apparent is United face competition for either shot-stopper, with three clubs reportedly in the hunt for Oblak's signature