Louis van Gaal and Angel Di Maria give Manchester United a chilling warning from history

Atletico Madrid confirmed two things for Manchester United. Firstly, this squad despite its masses of talent is no match for a well-drilled team and, secondly, the summer rebuild is going to have to be the club's biggest since 2014.

Eight years ago, Louis van Gaal arrived as manager after the departure of David Moyes, fresh from leading the Netherlands to third place at the World Cup in Brazil. The appointment signalled a change of tactic - Van Gaal had clear ideas about how he wanted the game to be played and he would need specific players of his own choosing to suit those needs.

His first window saw the incoming transfers of Luke Shaw, Ander Herrera, Angel Di Maria, Marcus Rojo, Daley Blind and Victor Valdes, with Radamel Falcao also joining on loan. After Moyes' two transfers across the summer and winter window during his doomed tenure, this sort of outlay was enough to get the United fanbase excited. But then it all fell apart.

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Just why did it all fall apart though under Van Gaal and what are the lessons that United need to learn ahead of what could be their biggest rebuild yet. And from two years under the Dutchman, there are two things to consider.

A problematic second close season

Bar the unfortunate issues with Di Maria and Falcao not being fully match-fit after his long lay off with injury the season before (and there's not really any point talking about Valdes) most of the players bought by Van Gaal in his first season became longstanding members of the squad and were useful after the Dutchman left the club. This shows good recruitment.

However, the second summer window was far more problematic. In an interview with FourFourTwo, Van Gaal