Your team can participate in several different competitions and tournaments in Rocking Soccer. These tournaments are based on the real life soccer world.
The most important competition is your league. You'll play 30-39 matches in your league in a season depending on the size of the leagues in your country
Besides the league you can participate in friendly matches, the national cup (a knockout tournament with teams from all leagues in your country), or one of the prestigious international tournaments
Each tournament has it's own counter for how many matches your players can get experience in this tournament. For example, a player can get experience in 20 league matches, but also in 3 cup matches and 6 friendlies. The amount of experience a player gets per match also differs for each tournament.
The exception are the U21 matches. These matches use the experience of the "senior" counterpart. U21 league matches count for the match counter of the normal league. That means that a player who played 14 U21 league matches can only get experience in 6 more league matches (U21 or normal).