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The J1 League is the top tier of professional football in Japan. Urawa Red Diamonds compete in this league, which is organized by the Japan Professional Football League (J.League). The J1 League was established in 1993 and consists of 18 teams. Urawa Red Diamonds have been a member of the J1 League since its inception and have won the league title three times, in 2006, 2007, and 2015.