The first big roster move of the Buffalo Bills’ preseason came today, and boy was it a doozie:

First shocking preseason cut: Buffalo Bills planning to release RB Karlos Williams, per league source. — Adam Schefter (@AdamSchefter) August 20, 2016

#Bills have made release of Karlos Williams official. I like Jon Williams and Gillislee fine, but think running game just declined a notch — Thad Brown (@thadbrown7) August 20, 2016

Williams had plenty of issues this offseason. First, he came into minicamp about twenty pounds overweight. He did slim down, but by that time he had moved on to a more serious issue: a four-game suspension for violating the league’s substance abuse policy.

Williams was a very productive runner last year, notching 517 yards and seven touchdowns on 93 carries. That included an NFL-record-tying streak of touchdowns in his first six games. He missed five games with a concussion but didn’t seem to have any related effects during the offseason (which isn’t worth much but still notable).

That said, the Bills have a quality stable of running backs moving forward. Mike Gillislee has apparently cemented his meteoric rise from P-squad castoff to bona-fide backup running back, and the recent addition of Reggie Bush, presumably as a return specialist, gives the team another capable hand in the backfield. Jonathan Williams presumably has a spot on the roster, and the team also has Boom Herron and James WIlder, Jr. on hand for the time being.

That said, it’s still a shock to see a young player who played so well find himself unemployed before his second year. He made some poor decisions that made it an understandable decision to cut him loose, although from the looks of things that didn’t have a whole lot to do with it.

Hearing #Bills decision to cut Karlos Williams is strictly based on performance. — John Wawrow (@john_wawrow) August 20, 2016

Whatever the reason, it’s an unexpected situation that probably won’t go over well if he moves on to another team and continues to rise, especially if LeSean McCoy and the remaining backs don’t maintain their league-best pace from last season.