The American cyclist decided Wednesday to try to regain his championship at the Court of Arbitration for Sport — the top court for sports — hoping arbitrators there will reverse an earlier decision to ban him for two years and strip him of his title for using performance-enhancing drugs.

"I hope that the arbitrators of the case will fairly address the facts showing that the French laboratory made mistakes, which resulted in a false positive," Landis said. "Although the process of proving my innocence has been difficult for me and my family, I will not stop trying to prove my innocence."

The CAS confirmed today that it had received Landis' appeal.

"The American rider requests the CAS to annul the AAA decision," the court said in a brief statement.

Landis will, once again, be an underdog in this case, just as he was when he went into the first arbitration hearing, and when he began his sensational comeback during Stage 17 of last year's race. The appeal surely will cost hundreds of thousands of dollars, though probably not millions, because much of the evidence already has been established and heard.

Travis Tygart, the CEO for the U.S. Anti-Doping Agency, said he couldn't guess on the cost of the appeal until he had seen some of the legal filings in the case.

"Of course, we'd prefer that our resources be devoted to supporting clean athletes," Tygart said.

A three-person CAS panel, appointed from a pool of international arbitrators, is expected to begin the hearing within three to six months. The same parties — USADA attorneys and the Landis camp, led by attorney Maurice Suh — will present their cases in what is expected to be a closed hearing in Lausanne, Switzerland, after which the CAS arbitrators will issue a final decision.

Last month, a panel sponsored by the American Arbitration Association ruled against Landis, upholding the results of a test that showed he used synthetic testosterone to fuel his spectacular comeback Tour victory. That decision meant Landis had to forfeit his title and is subject to a two-year ban, retroactive to Jan. 30.

A ceremony is scheduled Monday in Madrid, where Landis' yellow jersey will be awarded to second-place finisher Oscar Pereiro. The International Cycling Union declared Pereiro the winner a day after last month's ruling.

If Landis loses his final appeal, he'll remain the first person in the 105-year history of the Tour to lose the title because of a doping offense.

The arbitrators ruled against Landis even though they found numerous problems with procedures followed at the French lab that analyzed his urine.

Suh said he doesn't expect those errors to play too big a factor in the appeal.

"Properly applied, the recording of substantial errors without rebuttal from USADA should have resulted in Floyd being vindicated," Suh said. "So, once you get to this point, it's difficult to take too much comfort from their statements."

In a news release on the Floyd Fairness Fund Web site, Landis said: "Knowing that the accusations against me are simply wrong, and having risked all my energy and resources — including those of my family, friends and supporters — to show clearly that I won the 2006 Tour de France fair and square, I will continue to fight for what I know is right."

After the Sept. 20 ruling, Landis said he was unsure if he would appeal, not knowing if he wanted to spend another $2 million and the untold emotional cost of going through the process again.

But the cyclist has decided to press on.

"I think it has been the result of a relatively careful process of looking at alternatives and what Floyd wants to do," Suh said. "It's balancing his desire to try to vindicate himself against the cost and emotional toll it's taken.

"But ultimately, Floyd is a fighter, and he just felt the (arbitration) decision was not an accurate reflection of what facts were or what law is. That's what ultimately motivated him."

Suh said Landis had not yet decided whether he again would barnstorm the country to raise money for his legal defense.

In the original case, the arbitrators voted 2-1 again Landis. In their 84-page decision, the majority found the initial screening test to measure Landis' testosterone levels — the testosterone-to-epitestosterone test — was not done according to World Anti-Doping Agency rules.