Carra reckons Arsenal are yet to prove themselves in big games.
"I think it's going to be a season of up and down results, but Arsenal are top of the table and deservedly so. They've got to go and do something against Man City for everyone to sit up and take notice.
"I never really fancy Arsenal in the big games, especially away from home. They go to go to Old Trafford in a couple of weeks - let's have a look at them again then.
"If they lose that game, I'm not saying it's over, or they're finished, but I'd like them to go and start winning bigger, more important games," he told Sky Sports.