Rivaldo Vítor Borba Ferreira, Known as Rivaldo is backs ''brilliant'' Fred to deliver for Manchester United

Brazilian midfielder Fred will need time to adapt to the demands of English football but has all the attributes to succeed at Manchester United, former World Player of the Year Rivaldo has said.

United confirmed on Tuesday that they have reached an agreement with Shakhtar Donetsk to sign Fred for a British media reported fee of 52 million pounds ($69.72 million).

The 25-year-old has made eight appearances for Brazil and was named in the county`s 23-man squad for the World Cup, and Rivaldo reckons his compatriot could be the missing piece of United`s midfield jigsaw.

"He is a wonderful player," Rivaldo, who was part of Brazil`s World Cup winning team in 2002.

"Like any other player when you move to a new country, he will need a little bit of time to adapt.

"But when you are a good player and a brilliant midfielder like he is, he is going to do well and he is going to be good for Manchester United and they will be good for him."

United boss Jose Mourinho is looking to strengthen his midfield following the retirement of Michael Carrick and the uncertainty over the future of Marouane Fellaini at Old Trafford.