In Rocket League there are three online modes: a competitive mode, a casual mode and an extras mode. Competitive matches are usually formed by a similar difficulty level; players at the same levels or mixture of levels can usually be found player against one another. In casual, however, there doesn't seem to be an sort of ranking system involved. Surprisingly, these matches are usually fairly balanced. There must be some sort of system in place to ensure fair casual game play.
How are players in casual games matched?