BUFFALO, N.Y. (AP) -- The Buffalo Bills can't get a break even when they're off.
Starting linebacker Kiko Alonso sustained what the team fears to be a serious knee injury while working out in Oregon.
General manager Doug Whaley announced Alonso had been hurt, in a statement released by the team Tuesday night.
''We do not have the details at this point, but early indications are that it may be significant,'' Whaley said.
Alonso's agent, Stephen Caric, said he was unable to comment.
It's unclear when or how the injury occurred. During the team's mandatory minicamp two weeks ago, Alonso had indicated he planned to spend part of the offseason working out at Oregon, where he played college and maintains a home.
The Bills are off until July 18, when players are scheduled to report for the start of training camp in suburban Rochester.
Alonso was an NFL defensive rookie of the year contender last season after being drafted Buffalo in the second round out of Oregon. He led Buffalo with 159 tackles, two fumble recoveries and tied for the team lead with four interceptions while barely missing a snap in playing all 16 games.
Alonso had hip surgery this offseason, which limited him in participating in spring practices.
After playing in the middle last season, Alonso was moving to the outside linebacker spot as part of the Bills' shift to a 4-3 defensive scheme under new coordinator Jim Schwartz. The switch was also sparked in part by the Bills' signing of run-stopping specialist Brandon Spikes, who is better suited to play in the middle.
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