Gerkus says Spurs boss Jose Mourinho is a big fan of the Russia international.
Dzyuba, 31, is well known to Gerkus, who was working for Zenit when they signed the Russia international from Spartak Moscow. Dzyuba would go on to become one of the most successful strikers in the Russian Premier League.
And Gerkus admits Dzyuba's form and reputation had brought him to the attention of Mourinho over the New Year.
“I know this is not bulls***," Gerkus is quoted by Sport-Express. “I know his agent, the man who did this.
"I know that Mourinho wanted Dzyuba. I know this for sure.
"Mourinho knows who Dzyuba is. He worked at the World Cup in Russia as a commentator on Russia Today and discussed, among other things, the Russian team. I think he knows very well the composition of the Russian team."
Gerkus, himself, is a mover-and-shaker in football and local Russian television, having built Liga-TV, which was created to sell media rights for the Russian Premier League.
Gerkus admits Mourinho saw the experienced Dzyuba as a player who could adjust quickly to English football and make an instant impact.
He continued: "I do not know all the details, but there was an option. Why did Jose need Dzyuba? Score goals, win matches. I think Artem would have scored 10 goals in a season, everyone would have been happy.
"Why not let him go? Zenit needed him. The club wants to win titles."
Interestingly, Dzyuba's contract with Zenit expires at the end of this month.
- update June 15