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Ulsan Hyundai Football Club, commonly known as Ulsan HD, competes in the K League 1, the top-tier professional football league in South Korea. The league consists of 12 teams and operates on a double round-robin format, with each team playing every other team twice during the season. Ulsan HD has been a consistent force in the K League 1, winning the championship title twice, in 2005 and 2022.