ESPN President John Skipper told a report posted today that a promotional trailer for PBSFrontline documentary investigating NFL concussions was the “catalyst” for ESPN‘s pulling out of its partnership with the project. The League Of Denial: The NFL’s Concussion Crisis trailer was screened at an August 6 media panel and unveiled without Skipper’s or ESPN’s approval. Skipper complained the video was “sensational” and made him “quite unhappy”. He didn’t like the tagline, “Get ready to change the way you see the game”, or the trailer’s final quote from a neuropathologist on the extent of brain injuries in the NFL, “I’m really wondering if every single football player doesn’t have this.” Media watchers say pressure from the NFL led to ESPN’s sudden withdrawal and now Skipper admits he was embarrassed by the Frontline docu. Here’s the trailer:

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