Washington running back Clinton Portis practiced on his sore knee and is ready to go. Receiver Santana Moss did a lot of sprints and little else. The health of two important parts of the Redskins offense took different paths Thursday as the team prepared for Sunday's game against the Detroit Lions. Portis has a bruised and slightly sprained right knee, the same knee that was beset by tendinitis for nearly all of training camp. Portis said he was surprised that his latest setback has caused so much drama. Moss, meanwhile, is dealing with a groin injury that could loom larger for the Redskins than Portis' ailment. If Portis can't play, at least the team can turn to Ladell Betts, who rushed for more than 1,100 yards last year. If Moss doesn't go, the possible options include James Thrash, Reche Caldwell, Keenan McCardell and Brandon Lloyd -- none of whom has a catch this year.