One of the NFL's most feeble offenses is almost certain to be without its star running back for at least a week and possibly longer. Larry Johnson, a two-time Pro Bowl player, has a sprained right foot and is highly questionable for Sunday's game against Denver, Kansas City coach Herm Edwards said Tuesday. Edwards declined to speculate on how long Johnson might be out, saying he did not have enough information. "He's got a swollen foot right now, so that's not good," he said.