Williams, who's still under contract with the Miami Dolphins, is expected to begin practicing with his new team Monday; the Argonauts open preseason play this weekend and start their regular season at home against Hamilton June 17. The 18-game regular season runs through late October.

"It hasn't been too often that I've heard kind words about me and my situation. ... It's really an uplifting feeling to be in this kind of environment," Williams said at a news conference in Toronto, after team officials introduced him warmly.

Williams, a former Heisman Trophy winner, missed Miami's first four games last year following his third positive test, and lost an appeal over the fourth — which carries a mandatory one-year ban. But the desire to continue playing and earning led him to Toronto, adding another chapter to the enigmatic player's resume.

"I'm a very positive person," Williams said. "I understand that in life, when you go through adversity it only gives you an opportunity to make the best of the situation. So I'm happy to be here in Toronto, having a chance to further my career on the football field."

Earlier Sunday, before the signing was formally announced, Dolphins coach Nick Saban issued a statement saying the team left the decision about playing in the CFL up to Williams.

The Dolphins have supported Williams throughout the suspension, but insisted on assurances that he'd be allowed to return to the team in 2007 — provided he's reinstated by the NFL.

"We expressed to Ricky our concerns about playing in Toronto in 2006," Saban said. "We are relying on assurances made by Ricky, his agent, the Toronto Argonauts, and the commissioner of the Canadian Football League that Ricky will return to the Dolphins in 2007.

"Based on these assurances and despite our concerns for Ricky playing in the CFL in 2006, we will leave it up to him to decide whether or not he will negotiate a contract to play for the Argonauts this year."

Williams — who said he will wear No. 27 instead of No. 34 in the CFL — thanked Saban and the Dolphins for allowing him to play in Toronto.

"I don't think there are very many benefits to the Dolphins, and I think that speaks volumes for the kind of guy that Nick Saban is and the Dolphins organization," Williams said.

Leigh Steinberg, Williams' agent, didn't immediately return a message left on his cell phone by The Associated Press. The Argonauts said he was on a family trip to Ireland.

The 29-year-old Williams wasted little time in getting settled in Toronto. He was shown on the Rogers Center videoboard at the White Sox-Blue Jays game Sunday wearing an Argonauts hat and was introduced as the team's newest player.

"I've learned to notice a good thing when it comes and not let it slip by. ... You obviously make money playing football than you do sitting at home," Williams said.

Williams still owes the Dolphins $8.6 million for breaching his contract when he retired shortly before training camp in 2004. He returned last year and, playing alongside first-round draft pick Ronnie Brown, rushed for 743 yards — averaging over 4 yards a carry — for the Dolphins.

"I noticed that in the CFL they don't use the backs as a receiving threat," Argonauts linebacker Lee Woodall, a two-time Pro Bowl selection and a veteran of more than a decade in the NFL, told The Toronto Sun for a Sunday story. "But I'll tell you, if the Argos get Ricky, that's one of the factors you can put on your plate."

Toronto has won the Grey Cup — the CFL championship — 15 times, most recently in 2004. The Argonauts were 11-7 last season and are led by veteran quarterback Damon Allen, the brother of Pro Football Hall of Fame running back Marcus Allen.

Damon Allen, who has more than two decades of CFL experience, threw for 5,082 yards, ran for 461 more and had 37 touchdowns last season while earning the league's Most Outstanding Player award.

Williams said he's been asked several times why he wanted to play in the CFL. He said his answer was always, "Why not?"

"I feel like I have a lot to offer," Williams said. "I have the right attitude. I'm looking forward to this year."