Bryan Robson
Robson is one a series of legendary players to wear the No.7 shirt.

Manchester United legend Bryan Robson has called on manager David Moyes to sign a player worthy of filling the club's vacant No.7 shirt - formerly worn by Eric Cantona, David Beckham and Cristiano Ronaldo.

Antonio Valencia has recently vacated the shirt ahead of the new season, returning to his former number 25, leaving the shirt worn by a series of Old Trafford legends unoccupied.

George Best, Robson, Cantona, Beckham and Ronaldo comprise the pantheon of greats to have worn the famous number, and the former skipper says with the shirt once again vacant, United boss Moyes should splash out on filling the void.

"For me, if we can sign a player who is capable of wearing that no.7, like a David Beckham or Cristiano Ronaldo, then great," Robson told ManUtd.com. "Hopefully, it could be Ronaldo again"

After an inauspicious campaign last season, Valencia has opted to return to his favoured 25 shirt which he first wore upon his move from Wigan Athletic after finding the history behind the United No.7 shirt too much to bare.

Valencia's form has immediately improved, with a goal and an assist against Bayer Leverkusen in the Champions League representing a timely return to form for United, and Robson says he understands why the Ecuadorian made the change.

"I just think Antonio has been very honest," Robson added. "Maybe he did feel a little bit of pressure when wearing the number seven.

"He won Player of the Year when he wore no.25 and, after an indifferent season for him, when he didn't always show the quality we know he's got, maybe there's a little bit of superstition to go back to the shirt he was wearing.

"So it's a good decision and a strong decision by him. I think he's started the season pretty well so that is good for the club and good for Antonio."

Valencia was celebrating in mid-week after his Ecuador team secured qualification for the 2014 World Cup in Brazil despite a 2-1 defeat to Chile.