The Cowboys extended the contract of DE Sean Lissemore Thursday, adding three years and $3.1 million in guarantees to the deal, according to the team’s website. The third-year lineman’s previous contract ran through the 2013 season. Lissemore saw time in all 16 games in 2011 as a rotational player, tallying 28 tackles and two sacks, and rotated with DT Josh Brent to fill in for injured DT Jay Ratliff at nose tackle last week against the Giants. The Cowboys drafted Lissemore in the seventh round of the 2010 draft. Source: Pro Football Weekly