After the unification of the supporters of Leon Trotsky and Grigory Zinoviev, which took place in the spring of 1926, Evdokimov became an active participant in the "United Opposition." On April 9, 1926, G.E. Evdokimov was relieved of the post of secretary and member of the Orgburo, on November 14, 1927, he was removed from the Central Committee of the CPSU (b). Almost simultaneously, other leaders of the Trotskyite-Zinoviev bloc were removed from the Central Committee. At the 15th Congress of the CPSU (b) in December 1927 Evdokimov was expelled from the party.