Redknapp told the Daily Mail: "It will bother him that Craig Bellamy ran away from him to score in the Manchester derby. It's not so much the original mistake, but what happened after that. Bellamy is lightning quick, but Rio won't be used to players sprinting clear of him.
"The top level of international football is about dealing with pace and movement.
"Teams like Spain will try to cut you with their passing, down the side of your centre backs, for their runners to move into shooting positions.
"Because Ferdinand is quick, with those long legs and his elegant stride, he will recover his position, even after a momentary lapse in concentration, when he is on top of his game.
"Rio knows he needs to return to the training ground, assess his game, get his feet moving again, rediscover his trust in his body and fitness.
"Then he will emerge from this run of poor form. I know what it's like when you are masking an injury and your game suffers."