His place on the event’s card was taken by Afghan-born Briton Farid Basharat, who will share the octagon with Jackson on June 22 in the Saudi capital of Riyadh.
The substitution was reported by informed sources close to the situation. Why the Russian withdrew from the fight was not specified.
Montel Jackson, 31, is riding a four-fight win streak, having knocked out Rani Yaya in the first round in his last fight.
Undefeated 26-year-old Farid Basharat has won three fights in the UFC, most recently defeating Taylor Lapilus by unanimous decision.
Said Nurmagomedov, 32, put his career back on track last October with a first-round guillotine choke finish of Muin Gafurov. Prior to that, the Russian fighter snapped his own four-fight win streak by losing by unanimous decision to Jonathan Martinez.