Featherweights added to UFC 155
The bout takes place at the promotion's year-end event in Las Vegas, Nevada, set for Dec. 29.
UFC officials announced the fight on Monday.
Koch was originally supposed to fight earlier this month at UFC 153 against featherweight champion Jose Aldo, but his title aspirations were momentarily dashed after an injury forced him off the card.
Meanwhile, Lamas is a perfect 3-0 in the UFC, making this match up a potential top contender eliminator.
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