Holdout Emmitt Smith may be missing from the Dallas Cowboys lineup for Sunday's Super Bowl rematch with the Buffalo Bills, but the Bills may have their own missing star: Jim Kelly. Kelly said his right knee is sore and that he is scheduled for a magnetic resonance imaging test today to see whether arthroscopic surgery would be necessary. "If I had to play today, I couldn't because it's very painful," Kelly said after sitting out practice Wednesday afternoon. Coach Marv Levy said the Bills will wait for the results of the MRI before making any decisions about Kelly. "And we'll wait to see how Jim is feeling," Levy said. "If he's not feeling any better than he is right now, then he wouldn't play." Kelly sprained his right knee twice last season, the second time during Buffalo's 52-17 loss to the Cowboys in the Super Bowl. It was determined after the second injury that no surgery was needed, and Kelly underwent an arduous rehabilitation program. In fact, Kelly speculated that the large amount of running he has been doing may have caused the current discomfort. Kelly said a hit in Buffalo's 38-14 season-opening victory against New England may have exacerbated the injury. Kelly speculated that there "might be some fragments of cartilage that are left in there that are what's irritating it." If so, Kelly said he would lean toward having the operation done quickly. If that happens, Kelly would be expected to miss at least three weeks. The Bills have their first bye week after the Cowboys game, and Kelly said he might consider postponing any operation until after the Dallas game. Montana rests wrist KANSAS CITY _ Joe Montana didn't practice because of a sore wrist and was listed as questionable by the Kansas City Chiefs for the game Sunday against Houston. Montana spent the day doing squeezing exercises with his throwing hand. He was hurt in the third quarter of the Chiefs' opener Sunday at Tampa. Chiefs coach Marty Schottenheimer said Montana was held out as a precautionary measure. Schottenheimer said Montana would not practice until Friday. Dave Krieg, who replaced Montana against Tampa Bay, will start if Montana is unable to play. Around the camps Patriots: Guard Rich Baldinger practiced for the first time and could start Sunday against the Detroit Lions. Baldinger was released by the Kansas City Chiefs last week. Eagles: Guard Tom McHale and linebacker Louis Cooper were added to the roster after offensive lineman Rob Selby went on injured reserve and linebacker Ivan Caesar was waived. Browns: The team signed defensive back Louis Riddick and released defensive lineman Ernie Logan. The Browns also waived defensive back Curtis Cotton off injured reserve. Redskins: Offensive tackle Moe Elewonibi was taken to a hospital with a staph infection in his right elbow and forearm.