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Martin Kampmann was the opponent Jake Shields faced in his UFC debut. Shields, a renowned grappler, made his UFC debut in 2010 after a successful career in other organizations. Kampmann, a skilled striker with a strong wrestling background, presented a formidable challenge for Shields. The fight showcased Shields's grappling prowess as he ultimately submitted Kampmann via armbar in the second round, demonstrating his dominance in the ground game.