A doping scandal has rocked yet another sport — this time, the competition that calls itself the “Last Great Race on Earth” — the Iditarod Trail Sled Dog Race.

Officials with the 1,000-mile race through Alaska’s treacherous wilderness, two weeks ago announced that several dogs from one musher’s team tested positive for the opioid pain reliever Tramadol. It is the first time in the history of the world-famous race that dogs have tested positive for a banned drug. But the governing board declined to name the musher, leading to weeks of speculation.

On Monday, race officials revealed that the musher whose dogs tested positive was a four-time Iditarod champion, Dallas Seavey.

Seavey, 30, hails from a family widely considered mushing royalty, with deep ties to Iditarod history. He became the youngest Iditarod champion at age 25, winning the race in 2012, 2014, 2015 and 2016. This year, he finished second to his biggest competitor — his father, Mitch Seavey, a three-time champion and the oldest in history, at age 57. His grandfather, Dan Seavey, competed in the first Iditarod race in 1973.

Officials with the Iditarod Trail Committee said four of Seavey’s dogs tested positive for Tramadol after the finish of this year’s race in March in Nome. But they determined there was no way to prove the musher intentionally administered the drugs, so the musher would not face any punishment.

After his name was disclosed, Dallas Seavey announced he had withdrawn his name from the 2018 race in protest. He also spoke out about the doping scandal, saying he had done “absolutely nothing wrong.”

“I have never knowingly broken any race rule,” Seavey said in a 17-minute-long YouTube video. “I have never given any banned substance to my dogs.”

“They can try to throw me under the bus, but I’m going to be honest to myself,” Seavey added, “and they’re going to find out I don’t fit under the bus.”

He said he believed the drugs were given to his dogs maliciously, as an act of sabotage.

He has also argued that it would have been irrational for him to dope his dogs, because he knew they would be subjected to mandatory testing in Nome. He had even agreed to participate in additional voluntary blood tests. Moreover, the Tramadol would not, in his opinion, have given him a competitive advantage.

Tramadol is a Class IV opioid pain reliever that’s available by prescription only in pill, liquid, suppository and other forms. A drug testing team took urine samples from Seavey’s team about six hours after they had finished the race.

The Iditarod has been testing dogs for banned drugs since 1994, but only the top 20 finishers of the race are subject to testing in Nome.

During the past two weeks, pressure has mounted from within the Iditarod community to disclose the musher’s name. A union of mushers, the Iditarod​ ​Official​ ​Finishers​ ​Club, held an emergency meeting and demanded the release of the musher’s identity. In a statement, the group said it was “unacceptable” that the doping information was only recently made public, considering it was known since shortly after the March race.

The Iditarod Trail Committee chose to identify Seavey on Monday “because of the level of unhealthy speculation involved in this matter,” according to a statement.

The scandal has also prompted officials to change its rules over how to find fault for prohibited drugs.

The 2017 race rules required that officials prove the musher administered a banned drug. Moving forward, Iditarod rules will put the burden on mushers to prove their own innocence if their dogs test positively for drugs.

Even though Seavey was never disciplined, the musher criticized the governing body for not doing more to try to prove his innocence.

He mentioned the challenges of monitoring what a musher’s team of dogs ingests at all times. Unlike some other sporting events with animals, Seavey said, mushers are forced to leave their teams for lengthy spans of time during a race. At checkpoints, they sleep separate from their team. Because of this, he sees many possible opportunities for an individual to sabotage a team by injecting drugs into their food.

“The Iditarod says that we’re supposed to play detective now as well as racing,” Seavey said.

He urged race officials to boost security and surveillance cameras at various points during the race. The committee said its budget does not permit for such a “substantial cost” as that type of round-the-clock security, officials said in a statement.

The committee “believes that the mushers themselves can adopt practices which minimize any risks of tampering.”

Officials also said the idea that foul play could be involved in the doping of Seavey’s dogs is “not supported by identifiable facts but only by supposition and speculation.”

Seavey said he expected he would be banned from the race based on an Iditarod “gag rule.” It prohibits competitors from making public statements considered “injurious to and in reckless disregard of the best interests of the race,” including remarks that are “disparaging” to any sponsors.

The union of mushers also criticized this rule, calling for it to be eliminated entirely because it “makes mushers fear speaking out against the race of its policies for fear of retribution.”

The grueling trek pits mushers and their dogs against subzero temperatures in the Alaska Range and along the shore of the Bering Sea. From Anchorage to Nome, competitors traverse mountain ranges, frozen rivers and remote tundras.

The race was established in part to highlight sled-dog culture and to preserve the history of the Iditarod Trail. It also commemorates a famous 1925 mission in which a team of 20 mushers and 150 sled dogs ran in relays across Alaska to transport antitoxin to Nome, which was threatened by a large diphtheria epidemic. The sled dogs made the trip in 5½ days, helping to save the small town of Nome. The lead dog, Balto, became a celebrity — a statue of him was even erected in Central Park in New York City.

But the world-famous race is also a controversial one, particularly for animal rights activists.

Last year, five dogs died in connection to the Iditarod. The year before, a snowmobile driver who said he was drunk plowed into two dog teams, killing one dog and injuring three others.

People for the Ethical Treatment of Animals, commonly known as PETA, is a vocal critic of the race, which it considers cruel. It called on the race to stop using dogs altogether and replace them with snowmobiles or human athletes. Following the news of the doping case, PETA urged Iditarod officials to “strip all mushers found to have drugged dogs of their titles and awards.”

“It’s no surprise that someone used the prohibited drug to mask their pain and force them to keep running,” PETA wrote on its website.

The Seaveys, who have been a family force in the Iditarod for generations, vehemently contradict that view. Their family’s motto? “Take care of your dogs, and they’ll take care of you,” according to their website.

Dallas Seavey and his father have a rivalry that is “unprecedented” in the Iditarod, the Alaska News Dispatch reporter. “Never before in the race’s 44 years has a father-son tandem battled for the title,” the newspaper wrote.

The father and son are close, or as Seavey told the News Dispatch, “as close as you can be to someone like him.”

Certain topics are off-limits for the competitive duo. They live down the street from each other in the sparsely populated town of Willow. Mitch Seavey joked to the News Dispatch that he will someday plant spies at his son’s kennel, which Dallas Seavey founded with his wife.

“I will never let him win,” Mitch Seavey told the newspaper, adding he would fight him “tooth and nail to the finish line.”

Dallas Seavey was previously a USA Wrestling national champion before he committed to sled dog racing.

“I’ll keep on racing the Iditarod as long as that’s the thing I want to do more than anything else,” Dallas Seavey told the ADN earlier this year, before the doping scandal emerged. But, he said, “as soon as I find myself racing for one more win or a record, I’m doing it for the wrong reasons and that’s the time we need a change of scenery.”

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