DAVIE, Fla. -- The Miami Herald is reporting that Dolphins running back Ricky Williams has once again violated the NFL's substance abuse policy and is facing a one-year suspension.

According to reports, Williams faces a one-year suspension for violating the league's substance abuse policy for the fourth time in his seven-year career.

It does not mean that Williams necessarily failed a drug test, but that he might not have taken a required test.

Former Dolphins wide receiver O.J. McDuffie said Williams' reported drug lapse is a letdown for any Miami fan.

"After last season, they accepted him back," McDuffie told Local 10. "They love Ricky and what he did on the field, and now everybody's hurt again. So it's been an emotional roller coaster for the fans and, I'm sure, the teammates."

Williams came to Miami in 2002 after three troubled seasons with the New Orleans Saints and led the league in rushing in his first season with the Dolphins.

The 1998 Heisman Trophy winner tested positive for marijuana in December 2003 and during the offseason in 2004, then abruptly retired shortly before the 2004 season.

The Dolphins finished that season 4-12 -- their worst record since the AFL-NFL merger in 1970.

He returned to the Dolphins in 2005 -- sitting out the first four games for violating the NFL's drug policy -- and split time in the backfield with first-round draft pick Ronnie Brown.

News of Williams' reported substance abuse violation initially came from a TV station in Denver, where the Dolphins were believed to have been shopping Williams around in the hopes of a trade with the Broncos.

Because of privacy laws, neither the Dolphins organization nor the NFL has commented on the reports.

Williams is in India and unavailable for comment.

"He quit on the team again," McDuffie said. "This is the second time he's quit on those guys and you couldn't have him back right now, because this is definitely the second time he's quit."