Cleveland Browns practice squad defensive end Keith Grennan was reportedly injured during a post-practice opportunity drill, according to a report from AOL Sports FanHouse.

Per the report, Grennan was injured badly. He'll require surgery to repair a ruptured patellar tendon and will be out at least eight months.

According to the article, Grennan was injured during coach Eric Mangini's regular post-practice drill for practice squad players and rookies to impress the coaching staff.

A similar incident occurred with Browns rookie running back James Davis incurring a season-ending shoulder injury earlier this season. The Browns were ultimately cleared of any wrongdoing by the NFL.

In this case, Grennan was apparently wearing pads unlike Davis.

"We'll look into it," NFLPA spokesman George Atallah said.

There was no immediate reaction from the Browns.

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