Ferdinand backs big brother Rio

Anton (left) says criticism of his brother Rio (right) is unjustified

Sunderland defender Anton Ferdinand says older brother Rio will overcome doubts about his fitness and form and return stronger than ever.

Manchester United defender Rio has come in for criticism about his form lately and is struggling with a calf injury which shows no sign of improving.

"I know my brother and he'll come back stronger than ever," said Anton.

"People are doubting him for the World Cup - it's astonishing, he's been England's best player at the last two."

Rio Ferdinand, 31, has become a key player for Manchester United since his move from Leeds in 2002, but he missed the first month of the season with a torn thigh muscle and since then has had calf problems.

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Some of his recent performances for United and England have come in for criticism, but brother Anton, 24, said his brother was being unfairly criticised for slipping from his own high standards.

"This is the first time he's had a bad period since he left West Ham (in 2000) - for a player who has played so many big games to only have one bad patch in a 10-11 year period says something," he said.

"He's one of the best - he knows this would always happen, the minute he doesn't play well people will jump on his back."