I absolutely love NFL Films. But sometimes they have issues with identifying what year a film was made.
"They Call it Pro Football" was once identified, on "This is the NFL" (I think that was its name then) in the early '90s, as having been released in 1966. But there's a montage in the beginning from Super Bowl I, which of course was played on Jan. 15, 1967. In a couple of interviews in recent years, Steve Sabol has been quoted as saying they made it in 1965.
They have recycled some program titles, so I can't say with certainty that they didn't make a film in 1965 titled "They Call It Pro Football." But the one with narration by John Facenda, music by Sam Spence and the ground-breaking editing of Yoshio Kishi couldn't have been made before 1967, since it has the Super Bowl I footage.
But that's such a miniscule nit to pick: As Sabol said in the "Lost Treasures of NFL Films" episode "NFL Films Style," when they brought together Spence and Facenda for the first time, they knew they were on to something. Plus, they'd made the boss really happy: Sabol quotes Pete Rozelle as saying, after the film premiered at the Huntington Hartford Theater, "That's not a highlight film. That's a movie."