Cincinnati Bengals defensive end Carlos Dunlap will miss at least four weeks because of a sprained knee, the Cincinnati Enquirer reported Sunday. Dunlap, who was on crutches Sunday, said the injury occurred during Friday's 17-6 preseason victory over the New York Jets when Jets receiver Patrick Turner fell onto Dunlap's knee. Dunlap does not believe he will need surgery. Last year he didn't play in any preseason games because of a foot injury, and two years ago, as a rookie, he missed two preseason games and the first two regular-season games with a strained knee. He played in 12 games last season, including one start, and had 4.5 sacks. He had 9.5 sacks in 2010. Dunlap was working with the first-team defense this year. If Dunlap is out for four weeks, he would miss the Sept. 10 opener at Baltimore. Also, running back BenJarvus Green-Ellis did not practice Sunday because of a sore foot and is likely to miss Thursday's preseason game.