Germany's players been playing with this controversial new adidas ball for months.
Carra took in their 4-0 thumping of Australia and said: "I can see the headlines.
"It gives them an advantage anyway. That is obvious. We were sitting there last night and that is exactly what we were saying.
"The ball is very different. Every training session we do, we always start by passing 30 or 40 yards to each other just for that reason alone.
"I am sure it has helped them (Germany). It is an advantage, of course. I've watched all the games. And when you are creating a ball for the World Cup the idea is to create more goals, I think. This one does strange things to make it a more exciting tournament.
"But every cross I have seen has been over-hit. It goes over the back post.
"It helps if you are training with it but it is a little bit inconsistent. Sometimes you don't really know what it is going to do when you are knocking balls to each other.
"Sometimes it goes straight on, other times it just deviates at the last minute. But that is the same for every team, probably except Germany."