Vin Diesel thinks a lot of his co-star, John Cena. In “F9: The Fast Saga”, the brother of Diesel’s character, Dominic Toretto, is introduced as Jakob and is portrayed by Cena.

While the former WWE star now seems like an obvious choice, Diesel admits on Wednesday’s episode of “The Kelly Clarkson Show” that he experienced some “anxiety” about casting the role of his sibling.

“Obviously I’m multicultural. You could’ve cast anybody to be my brother,” Diesel notes to host Clarkson. “…For two months before I went into filming, I created a shrine where I could do all the combat training, all the stunts and I had the Charger there to simulate the garage to get into the Dom state of mind.”

The action star continues, “Now the idea of the brother worked great on paper, but when the time came to cast it, anxiety. Who could you cast to be Dom’s brother and 20 years into the game? The audience knows our mythology so much.”

Enter Cena. “And he comes into the shrine one morning,” Diesel recalls. “…And I had this strange feeling that Paul Walker had sent him.”

Walker portrayed Brian O’Conner for seven “Fast & Furious” movies, but tragically died in a car accident in 2013. He was 40.

Diesel recently told ET’s Nischelle Turner that every “Fast” film going forward will pay tribute to Walker, who he affectionately refers to as Pablo. “That does absolutely have to happen,” he said. “I can’t envision making a ‘Fast’ film, continuing this mythology without my brother, Pablo’s, soul being the guiding spirit.”

“F9: The Fast Saga” hits theatres in the U.S. on Friday.

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