Buffalo Bills cornerback Leodis McKelvin suffered a fractured ankle in Week 11 of last season, but he was expected to be ready for the start of the upcoming season. That has since changed after McKelvin suffered a setback in his rehab process.

Even after the setback, the Bills believed McKelvin would be ready for Week 1, but Rex Ryan backtracked on those comments on Thursday. Ryan told reporters that the Bills underestimated the setback and McKelvin's status for the start of the season is up in the air.

McKelvin missed the final six games of the season, but still recorded four interceptions to lead the team in that category. He's an integral part of the defense and was expected to start alongside Stephon Gilmore at cornerback.

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Rookie Ronald Darby has stepped in and played well in McKelvin's absence and could be in line to be the second starter for the regular season. This could be a big blow to the Bills' defense, which is expected to be one of the best in the league.

(h/t Twitter)