The New England Patriots were hit with some tough news on Sunday, including a development that top running back Dion Lewis, who had been rehabbing from a torn ACL suffered last season, will need a second knee surgery.

According to the Boston Globe's Jim McBride, Lewis needs a second surgery, after having his knee repaired last season.

ESPN NFL Insider Adam Schefter called the impending second surgery a "clean up" procedure, adding that there is still a possibility for Lewis to return at some point this season.

The 25-year-old started training camp on the physically unable to perform list, though he had participated in some drills towards the end of the team's organized team activities earlier this summer.

Lewis, who was in his first year with the Patriots last season, had been a key part of the team's offensive game plan prior to his injury in a Week nine win over the Washington Redskins. In seven games last season he rushed for 234 yards and totaled 388 receiving yards, as the team's primary option out of the backfield.

pass-catching back James White filled the void in Lewis' absence last season, in the New England pass first offense. He'll look to get an elevated role right out of camp again this year, while backfield veterans LaGarrette Blount and Brandon Bolden probably step into bigger roles as well.

The injury may also open the door for youngster Tyler Gaffney, who spent his first two seasons in the league on the sidelines with injuries. Paying in his first two preseason games this year for the Pats, Gaffney has impressed with a hard-nosed running style and shifty moves out of the backfield.