Millwall was one of the founding members of the Southern League in 1894. They competed in it for 22 seasons until 1920, claiming the title twice in 1895 and 1896. Since joining the Football League in the 1920–21 season, the club have been promoted eleven times (five times as champions in 1928, 1938, 1962, 1988, and 2001) and relegated nine times. They have spent 88 of their 94 seasons in the Football League yo-yoing between the second and third tiers. The club did have a brief spell in the top flight between 1988 and 1990, in which they achieved their highest ever league finish of tenth place in the First Division in 1988–89. Millwall reached the 2004 FA Cup final and qualified for Europe for the first time in their history, playing in the UEFA Cup. The club have also won two League One play-off finals in 2010 and 2017, the Football League Group Cup in 1983, and were Football League Trophy finalists in 1999.