Mike Rodak of ESPN.com reported the team will save $3.9 million with McKelvin's release.
The 30-year-old veteran has been with the Bills since they selected him in the first round of the 2008 NFL draft, but his role changed significantly in 2015.
After shuttling in and out of the starting lineup at cornerback during his first seven seasons, he was definitively surpassed by Stephon Gilmore and rookie Ronald Darby on the depth chart.
When the Troy University product returned from an ankle injury midway through the campaign, he became a jack-of-all-trades as an occasional outside corner, slot corner, safety and punt returner. All told, he registered 32 tackles and two interceptions in nine contests.
Defensive back depth is key in the NFL due to the high volume of passing, and having a versatile player like McKelvin in the fold for 2016 could be a much bigger deal than it appears to be on paper.
Rapoport believes McKelvin will draw interest in a free-agent market that's thin at cornerback due to his starting experience.
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