Anthony Spencer to undergo season-ending knee surgery

Anthony Spencer's agent has confirmed that he will undergo a season-ending knee surgery.

The Dallas Cowboys defensive end missed part of the team's pre-season while recovering from a previous knee operation, before sitting out games against the Kansas City Chiefs and St Louis Rams.

The 29-year-old's agent, Jordan Woy, confirmed on Twitter that Spencer will need surgery, and that he should be "100%" by January or February.

Spencer made two tackles in his one game for the Cowboys this season.