Dolphins running back Ricky Williams faces at least a one-year suspension from the NFL after a fourth violation of the league's substance-abuse policy.
WSVN-TV and the Miami Herald reported that Williams failed the test, but the league would not confirm. On three previous occasions, the sixth-year veteran has tested positive for marijuana.
"Because of the confidential nature of the league's substance-abuse policy, we can't comment on any aspect of that program," Dolphins spokesman Harvey Greene said Sunday night.
Williams returned last fall after retiring for the 2004 season. He missed the first four games of the 2005 season and was fined an additional four weeks of salary from the second and third violations of the substance-abuse program. They occurred in December 2003 and the 2004 offseason.
Williams, who rushed for 743 yards in 168 attempts with six touchdowns in 12 games last season, has spent much of the offseason in northern California studying yoga and holistic medicine.
BETTIS IN THE BOOTH: Jerome Bettis joined NBC as a studio analyst for Sunday night games. "I am looking forward to this new opportunity and to still be involved in the game I love," he said. The former Pittsburgh running back retired after helping the Steelers beat the Seahawks 21-10 in the Super Bowl this month in his hometown of Detroit.
His first game will be in Pittsburgh on Thursday Sept. 7, when the Steelers receive their Super Bowl rings. "It will be the proudest night of my life," Bettis said. "I will finally get my ring and I will start my new career in television in front of all the Steelers fans."
He ended his playing career after 13 seasons, retiring as the NFL's No. 5 career rusher. In recent seasons, he was relegated to more short-yardage or goal-line situations. He finished with 43 yards on 14 carries in the Super Bowl.
AIKMAN ON FAVRE: Troy Aikman believes the Packers' struggles will likely drive quarterback Brett Favre into retirement.
"I'd hate to see him retire," Aikman said. "But I know that going out and having seasons like what he went through this past year is really frustrating and it just isn't much fun. So I don't know what he's going to do. I think the fact that he is having a hard time making the decision, in some ways, to me, that kind of has made the decision for him."
Favre hasn't said whether he will return to the Packers, who are coming off a 4-12 season, their only losing season with Favre.
"Over the years, Brett and I have talked a lot about kind of what happened at the end of my career, kind of where he's at right now," the former Cowboys quarterback said. "And Brett has drawn some comparisons to what he's currently going through with what I went through at the end of my career - not from a health standpoint, but just kind of where the team is."