Since 1984 the Terriers have played in the Hockey East conference, along with crosstown arch-rivals Boston College (BC). The series with Boston College is known as the Green Line Rivalry or the Battle of Commonwealth Avenue. Under long-time coach and former player, Jack Parker, BU excelled in the 1990s, winning six Hockey East regular season titles, four Hockey East tournament titles, the 1995 National Championship and three National runner-up trophies. BU missed the Frozen Four for 11 consecutive seasons beginning in 1998 but returned to glory by winning the national championship in 2009.