Chiefs quarterback Matt Cassel returned to the practice field Monday for the first time since hurting his knee on Aug. 29. His status for Kansas City's season opener against Baltimore is still unclear. Cassel injured his knee on the third play of the third preseason game against Seattle. He signed a six-year contract for a guaranteed $28 million after the Patriots traded him to the Chiefs. "I think that as the week goes on, we'll know a little bit more," coach Todd Haley said. "We'll know a little bit more with Matt for sure. But it was good that he was out there. He was able to get through some things. As the week goes on a little further, we'll know a little more as far as where he's at."