It's no secret that there is a pipeline connecting professional athletes to the broadcasting business.

The list of color commentators, analysts, sideline reporters and talk show hosts in sports includes many former athletes, as insight that comes from game experience and faces that fans recognize are valuable to networks.

This, as well as the chance to give former players job opportunities when their playing days come to end, are some of the reasons why the NFL hosts a "Broadcast Boot Camp."

Unlike the types of training camps players are used to, the NFL describes broadcast boot camp as, "A four-day [event], co-directed by the NFL Player Engagement and NFL broadcasting departments, cover[ing] a wide range of topics with instructors from top broadcast and radio networks, including Big Ten Network, CBS, ESPN, FOX, NBC, NFL Network, SiriusXM, and Westwood One Radio. Sessions include hands-on work in areas such as tape study, editing, studio and show preparation, radio production, production meetings, and field reporting."

According to the NFL, three former Patriots are among the attendees: defensive back Darius Butler, quarterback Matt Cassel, and running back Shane Vereen.

Butler played for the Patriots from 2009 to 2010. Cassel was the Patriots' backup quarterback from 2005 to 2008. When Tom Brady missed the 2008 season with a torn ACL, Cassel took over, leading the Patriots to an 11-5 record.

Vereen played for the team 2011 to 2014, helping power the Patriots' Super Bowl run in 2014, the team's first Super Bowl title since 2004.

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