The bout, which led the league’s final event of the year, ended at 1:27 of the second round after Reznikov moved Koshkin, went to a north-south crown choke, and forced the opponent to signal surrender.
After the fight, Artem Reznikov had a battle of views with the Russian Eduard Vartanyan, who last month won an early victory over his compatriot Yusuf Raisov in the first semifinal match.
After a tense shutdown, both Grand Prix finalists who will meet next year have vowed not to go to a decision and end the fight in the first round.
All results of the ACA 150 tournament.