Gregory Nava cast Jennifer Lopez in her breakthrough role as Selena in the iconic 1997 film
Jennifer lopez
Jennifer Lopez; (Inset) Selena Quintanilla
| Credit: Amy Sussman/SHJ2019/WireImage. Inset: Getty Images

Jennifer Lopez's rise to stardom with 1997's Selena was aided by the late singer's spirit, director Gregory Nava believes.

Nava, 71, spoke to PEOPLE ahead of the Blu-ray release of Selena (out now) in which he recalled casting Lopez, 50, in the role of the legendary Tejano music singer, Selena Quintanilla.

"Jennifer's a very hard worker, everything she's earned in her career and her life she's earned from very hard work," says Nava. "She's a very great role model for all of us."

The film, which celebrated its 23rd anniversary in March 21, "is the birth of Jennifer's great stardom and the cementing of Selena's legacy and bringing her light to the world," Nava says. "This is extraordinary."

Nava says Lopez "studied" and "did her homework" on the legendary singer, leading him to believe while filming that there "was no doubt" the actress would nail the role.

"Jennifer's a very talented person. She's a great dancer, she's a great singer, but her greatest talent is as an actress," says Nava. "If you see them side by side, which they have on the internet comparisons of the two, [Lopez] imitated her perfectly, and really captured the way she moved."

Selena Quintanilla
Selena Quintanilla
| Credit: Houston Chronicle/AP

He adds, "All of that helped Jennifer channel her spirit. I think it's an example of the fact that the light and the spirit of Selena was with us. That's who made it happen, was Selena."

Nava also reveals why in the film he never showed the exact moment Selena was shot by Yolanda Saldivar, the singer's former fan club president who killed her.

"We see the violence [in films] but we don't see the consequences of the violence and that's wrong," says Nava. "The Greeks had it right. You see the consequences of this violence."

The director says he chose to focus on the consequences of Saldivar's actions, instead, including a scene of Lupe Ontiveros, who portrayed her, in a car crying on the phone with a negotiator, as well as scenes of the Quintanilla family mourning the loss of their daughter in the hospital.

He says 8,000 people arrived on the night he filmed Selena's death, including women and young girls who had been fans.

"I wanted to do it for those girls and for all of our community, to remember her and show that what lives on is her light and her spirit," says Nava. "I wanted to do everything I could to take this tragic situation and make it as positive as possible. I'm very proud of the ending of Selena. That light has now gone to the world with this film."

Selena is now available on Blu-ray.