SOCHI, Russia – Sweden’s star center Nicklas Backstrom wasn’t allowed to play in the gold medal game against Canada after testing positive for a banned substance.

An NHLPA source told Yahoo Sports that Backstrom violated anti-doping rules after tests showed an elevated level of pseudoephedrine, a banned substance by the IOC and the World Anti-Doping Federation.

Backstrom has taken Zyrtec-D for several years for allergies. He said he takes on pill per day.

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Backstrom was pulled from the locker room two hours before Sweden's pregame skate on Sunday, after being announced in the starting lineup. He had been tested last Wednesday.

“I got the message two hours before the game, that there was something wrong. Then I knew when the warmups are starting that he wasn’t going to play," said Swedish Coach Par Marts.

Mark Aubry, chief physician for IIHF, said that Backstrom wasn't attempting any doping and was using it as a cold medication. “There is no doping in this instance," he said. "He is an innocent victim. We support him strongly. Doping is not allowed, but this is not a case of doping.”

Pseudoephedrine is prohibited when its concentration in an athletes' urine is greater than 150 micrograms per milliliter. Backstrom's level was 190.

It was originally reported before the game that Backstrom, who plays for the Washington Capitals, would miss the gold medal match with a migraine, after he didn’t appear in the warmup.

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“I was watching the game in the Village," said Backstrom in a postgame press conference. "I’ve been here for two weeks. It’s probably the most fun two weeks I’ve ever had. I was ready to play, probably, the biggest game of my career,” said Backstrom. “It’s sad.”

Backstrom is Sweden’s top line center, with four assists in five games.

“It sucks. It’s like kindergarten," said Marts. "I can not ice the best team today. We should have the right conditions to compete with Canada and we didn’t have that today.”

Sweden lost to Canada, 3-0. It wasn't immediately known if Backstrom would receive a silver medal if the ruling was upheld.

The National Hockey League released a statement saying that high levels of pseudoephedrine are not currently on the League’s Prohibited Substances List, and hence Backstrom is in no danger of suspension when he returns to the NHL.