The Buffalo Bills have prevented cornerback/return specialist Leodis McKelvin from reaching the free-agent market, with the club announcing it has agreed to terms on a contract with the former first-round pick on Sunday.

Terms of the pact were not disclosed by the team, though the Buffalo News reported the deal to be for four years and worth more than $20 million, of which $7.5 million will be guaranteed.

McKelvin has spent his entire five-year career in Buffalo after being taken by the Bills with the 11th overall selection in the 2008 draft. The 27-year-old is regarded as one of the league's premier punt returners and led the NFL with an average of 18.7 yards per runback in that category this past season.

The Troy product also took back a franchise-record two punts for touchdowns in 2012 and has four return scores (3 punt, 1 kickoff) over the course of his career.

As a defender, McKelvin recorded 21 tackles, one interception and three passes defensed while starting four of 13 games last season. He has compiled six picks and 30 passes defensed over 64 career contests.