Minakov (14-0) defeated Kongo via unanimous decision at the Reno Events Center in Reno, Nev. All three judges scored the bout 48-46 for the champion.
"I fought the strongest in the division today," said Minakov, who won the title via knockout against Alexander Volkov last November. "Now I feel like a real champion."
It was an ugly, sluggish heavyweight affair for the most part. Kongo (20-9-2) had his moments, but was physically exhausted by the final round.
Referee Herb Dean stayed busy in the five-round title fight. He penalized Minakov a potentially crucial point in the first round for two accidental low blows. In the fourth round, he repeatedly warned Kongo for illegally grabbing Minakov's shorts.
The wrestling pedigree of Minakov impacted the result, as he dominated Kongo on the floor in the third and fifth rounds. He dropped him in the first with a right hand, but never came close to finishing the fight.
He hurt Kongo again in the second round with a short right hand to the temple. The Russian heavyweight scored a takedown moments later and eventually moved to full mount before the end of the frame.
Kongo landed a few early body kicks and secured top position for much of the fourth round, but was otherwise limited offensively. He complained to Dean in the second round about a Minakov knee to the groin, but replays verified the strike was legal.
The loss snaps a two-fight win streak for Kongo in the Bellator cage. The 38-year-old Frenchman signed with the promotion last year after an 18-fight career in the UFC.
The undefeated Minakov earns only the second decision victory of his career. It's the first time he has failed to finish an opponent since July 2010.
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