The O-League (aka OFC Champions League or Oceania Club Championship) is a continental football tournament held annually for Oceanian clubs, organized by the Oceania Football Confederation (OFC).
Began in 1999 with frequent name and format changes, it primarily existed to determine the Oceania qualifier at the FIFA Club World Cup. In 2007, the OFC replaced the Oceania Club Championship with the Oceania Champions League/O-League and FIFA determined the winner will no longer gain direct entry to the FIFA Club World Cup, but instead will play off against the host nation's (currently Japan) champion for a final spot. The tournament is played on a complete home-and-away basis as the winners of 2 groups of 3 clubs play the 2-legged finals.