Manchester United must act quickly if they're serious about signing Valencia midfielder Carlos Soler.

The youngster has been watched by United this season, with English media sources claiming he is a long-term target for manager Jose Mourinho.

However, it's emerged that Soler's buyout clause will quickly jump by the end of the campaign should he maintain his progress.

Soler's current escape clause is set at €8 million, but that will rise to €30 million if he can complete another eight first team games.

The midfielder has been one of the few bright points for Los Che over the past month.