'Mediocre Louis van Gaal is destroying Manchester United, Pedro should not go' says Hristo Stoichkov

Stoichkov, a five-time La Liga winner and European champion with Barcelona, fell out with Van Gaal in 1998 and says Pedro only needs to look at how the Dutchman has treated goalkeeper Victor Valdes after he made the switch.

Spain international Pedro is reportedly poised to move to United in search of more playing time with his opportunities at the Camp Nou having been limited, but Stoichkov has warned him against doing so in very strong terms.

"I would never be under the orders of Van Gaal," the 49-year-old told Spanish radio station Onda Cero.

"He's mediocre. He destroyed Barca and is destroying Manchester United.

"With what he has done to [Victor] Valdes he has shown he is a bad person. Hopefully Pedro listens to me and doesn't leave."

Stoichkov, who has previously branded Van Gaal as “scum” in an interview with French newspaper L’Equipe, has always said that he struggles to find anything good to say about his former manager.

"I have no respect for him," Stoichkov added.

"One day, when I was injured, I was with my wife at Camp Nou and Van Gaal went up to her.

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"He asked her how it was possible that she married someone like me. She responded that I was a Ballon d'Or winner.

"My departure in 1998 was the fault of Van Gaal, for sure."