Ivanov applied an Americana shoulder lock, forcing the former UFC and Strikeforce fighter to tap at the 4:08 of the first round.
“I feel amazing,” Ivanov said in his post-fight interview.
Johnson was the first to apply his offense in the match, throwing heavy punches as Ivanov curled up against the cage. The Bulgarian fighter then found an opportunity to clinch with Johnson, stopping the power shots.
Ivanov secured a single-leg takedown to bring the fight to the floor, and later attempted a foot lock. Johnson escaped and brought the fight back to the feet.
While clinching against the cage, Johnson picked up Ivanov and scored a body slam. Johnson was unable to keep control on the ground, allowing his opponent to return to a standing fight.
Ivanov later tossed Johnson to the ground and secured the submission that would bring an early end to the main event.
With the win, Ivanov will advance to the Bellator Heavyweight Tournament Final, where he will face Alexander Volkov, who won his tournament semifinal bout over Mighty Mo earlier in the evening.
In the co-main event on Friday, Joey Beltran picked up the second submission win in his professional career, locking on a north-south choke to defeat Vladimir Matyushenko.
Beltran stopped a takedown attempt by his opponent, securing top control and working towards the choke. The finish came at the 3:06 mark of the third round.
The fight was the last of Matyushenko’s career, making his retirement official in his post-fight interview.
Other main card results:
Adam McDonough def. Nathan Coy by TKO (punches) at 0:30, Round 2
Alexander Volkov def. Mighty Mo by knockout (head kick) at 2:44, Round 1
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