Dion Lewis' breakout season came to a sudden end in Week 9.

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New England Patriots running back Dion Lewis left Sunday's win with a non-contact knee injury, and on Monday, the team's biggest fear was confirmed.

After undergoing an MRI on his knee, Lewis was diagnosed with a torn ACL and will be out for the remainder of the season, as first reported by Jeff McBride of the Boston Globe.

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Lewis' left knee bent in a scary way when he made a cut in the middle of the field, falling to the turf immediately without making contact with another player. The original hope was that Lewis suffered just an MCL sprain, but unfortunately it was far more severe.

Just one month ago, Lewis signed a two-year deal worth up to $5 million, which is now very noteworthy. Had he not signed the extension, he may not have gotten the chance to sign such a lucrative deal after suffering a torn ACL.

In seven games, Lewis rushed for 234 yards on 49 attempts, and caught 36 passes for 388 yards. He scored a career-high four touchdowns this season and proved to be an integral part of the Patriots offense.

Brandon Bolden and James White are likely to assume Lewis' role in the passing game with LeGarrette Blount getting more carries as a workhorse back.

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