"Rio for me is one of the best young defenders in the world and he proved that in the World Cup," Beckham told MUTV.
"He has come to Manchester United now and I am sure that while that has upset a few people, he has made a few people here very happy."
Beckham praised Ferguson's skills at signing players that settle in quickly at Old Trafford. He said: "I have always said that the manager picks players who fit in when they come here."
"Whether that is luck or he means to do it all the time, he picks players who fit straight in with the rest of the lads."
"Rio being young he has fitted in with the lads he has played with for England and those he has played against,"