I must agree completely with the statement that Ed Sabol “revolutionized Pro football”.
John Facenda was the voice.
One night in 1965, Facenda went to a local tavern, the RDA Club, which happened to be showing footage produced by NFL Films. He enjoyed the slow-motion game sequences that were already an NFL Films trademark and would later recall:
I started to rhapsodize about how beautiful it was. Ed Sabol, the man who founded NFL Films, happened to be at the bar. He came up to me and asked, ‘If I give you a script, could you repeat what you just did?’ I said I would try.
Thus began Facenda’s association with NFL Films, one that would continue until his death. Facenda narrated many highlight films during his career with the company. His dulcet baritone was the perfect match for the highly dramatic nature of the footage he narrated, and earned him the nickname “The Voice of God.” Probably one of the best-remembered (and most frequently-quoted) examples of Facenda’s NFL Films narration is something he never actually said: “the frozen tundra of Lambeau Field” was a quote the sportscaster Chris Berman made up, mimicking Facenda’s voice when he said it. Steve Sabol, son of Ed, claimed that “John may have made a game seem more important than it was because he read lines with a dramatic directness”[2] Bob Costas called Facenda’s voice “one of the most remarkable instruments in the history of broadcasting.”
Facenda was the voice but Sam Spence wrote the music....classic collaboration here:
https://www.youtube.com/watch?v=qmJhSF86H9U