Report: Bob Costas reveals why he was kicked off NBC's Super Bowl broadcast

When NBC televised last year's Super Bowl between the Philadelphia Eagles and New England Patriots, the network's most recognizable sportscaster was nowhere to be seen. 

The reason, according to 40-year NBC Sports veteran Bob Costas, goes back to comments he made about the NFL's concussion problems more than two years earlier.

A lengthy report by ESPN's Outside the Lines delves into the details of an increasingly uneasy relationship between Costas and professional football -- and how it got him into trouble with his longtime employer.

In December 2015, as the movie "Concussion" was about to be released, NBC's Sunday Night Football broadcast was in Pittsburgh for a game between the Steelers and Indianapolis Colts.

As Costas was preparing his weekly halftime essay, he noted a connection with former Steelers great Mike Webster, who was a prominent figure in the movie.

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"It was a natural lead-in," Costas told OTL. "I thought that the movie would make an impact, and I thought this was a way not only for NBC to acknowledge it, but to get out in front of it."

He told ESPN he took the unusual step of submitting his essay in advance to NBC Sports execs.

But he was told he couldn't air it because the network was bidding for the NFL's Thursday Night Football package. 

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"It was at that point that I realized that this was an untenable situation for me," he said. "I knew my days there were numbered."

NBC officials chose not to comment, except to issue a statement saying the network was "very disappointed that after 40 years with NBC, he has chosen to mischaracterize and share these private interactions."

Fast forward to a few months before NBC would air the Super Bowl in February 2018. Costas continued to express his opinions in public forums. At the University of Maryland. On CNN.

Finally, NBC informed Costas, as he recalled to ESPN, that he'd "crossed the line" and was being taken off the Super Bowl broadcast. 

Although he couldn't point to one thing in particular -- he'd been outspoken about the dangers of concussions going back to 2010 -- Costas said he felt a sense of relief.

"My response was not, 'Oh please, please, change your mind,' " he told ESPN. "My response was, 'Yeah, I guess you're right.'"

Last month, word leaked out that the now 66-year-old Costas and NBC had agreed to part ways, even though he was still under contract through 2021. 

What he told USA TODAY Sports in August 2018 about his relationship with NBC Sports rang true once again: "What was once a perfect fit no longer fits that description.”

Follow Gardner on Twitter @SteveAGardner