Sir Bobby Charlton revealed why they had to sell Pique.

Sir Bobby Charlton says they had no choice but to sell Gerard Pique back to Barcelona.

Since the Spain defender left Old Trafford, he has won the Champions League and World Cup.

Charlton, a United director, explained: "At Manchester United, we knew he was already going to be great, but Sir Alex Ferguson had to let him go to Barca because the boy asked him.

"We all knew he would be a great player. I remember that before leaving Old Trafford he had shone in the Champions League and Premier League.

"He was very young but had everything to succeed, as he has now with Barca and with Spain in the World Cup."