Koreshkov made his professional mixed martial arts (MMA) debut in October 2010.

He initially competed exclusively in his native Russia and compiled an undefeated record of 8–0 (five technical knockouts, three submissions) with none of his fights going to a decision.

[6] In the semifinals of the tournament, Koreshkov won via Technical Knockout, defeating Marius Zaromskis in the first round.

Koreshkov was expected to face Sam Oropeza on May 2, 2014, in Welterweight tournament finals at Bellator 118.

[10] He won the fight via unanimous decision, securing his second tournament win and title shot.

[12] He dominated the fight, winning a unanimous decision and scoring his first title defense as the Bellator welterweight champion.

[17] He won the fight via knockout due to a spinning back kick to Bakocevic's mid-section early in the first round.

[25] While Bellator had no events booked for the beginning of 2021, Koreshkov faced Adriano Rodrigues at AMC Fight Nights: Sochi on February 23, 2021.

[35][36] Making a quick turnaround, Koreshkov was scheduled to face Paul Daley on May 13, 2022, at Bellator 281.

[38] With his last bout being canceled, Koreshkov, while still under contract with Bellator, faced Leonardo Cavalheiro on June 18, 2022, at Shlemenko Fighting Championship 4.

[43] Umalatov's power punching & wrestling proved to be effective against Koreshkov, who was close to getting finished during the fight, but managed to survive until the final bell and lost via unanimous decision.

[44] Koreshkov next faced Goiti Yamauchi at PFL 6 (2024) on June 28, 2024, winning the fight via unanimous decision.