Team spokesman Rodrigo Paiva said on Saturday that the equipment, which the goalkeeper wraps around his waist, contained metal clips but they had been approved by FIFA.
"The only thing which has metal are the clips," Paiva told reporters.
"It's a normal belt which he has used for the past two years at his club and with Brazil, to give him more confidence.
"Before the game, FIFA look at all the equipment and this was permitted because there wasn't a problem," he added.
The protector was exposed when Julio Cesar was treated on the pitch after being hurt in a clash with Raul Meireles during Friday's game.
It immediately caused speculation that he was still suffering from a back injury which he sustained during a friendly against Zimbabwe before the World Cup.
The player told reporters after Friday's game that he used the protector to give him more confidence and that he had completely recovered from the injury.
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