He has won the Scrabble national championship in the United Kingdom. Self-described as "the world's only scrabble consultant," he has penned or co-written a number of books on the game, including several authoritative reference works. And despite decades of high-level play, he showed few signs of slowing — maintaining a No. 5 ranking worldwide, according to one rating system.

Now, though, Allan Simmons has been banned for three years by the very association he helped found. What happened?

Simply put, the Association of British Scrabble Players found the Scottish Scrabble titan guilty of "actions that led to a suspicion of cheating," as quoted by the Times of London.

Put a little less simply ... well, we'll leave that explanation to the Times:

"At the heart of the controversy are the rules on selecting tiles from cloth bags used in timed matches. Before picking them, players must show opponents their palm with the fingers splayed to prove they are not secretly dropping unwanted letters into the bag.""They are also required to hold the opening of the bag at shoulder height to ensure they cannot be accused of looking at the tiles during selection."

According to fellow Scrabble player Lewis Mackay, Simmons failed to meet those standards. Mackay says he noticed something fishy while watching Simmons compete against another player in a 2016 match, noting in his complaint to the ABSP that "at one point, I was surprised to see him draw a tile, look at it, and return it to the bag, all at shoulder height. I thought I was seeing things at first — I was shocked to witness this at all.

"I said nothing to anyone at the time," Mackay said. "On reflection, perhaps I should have."

Mackay said his next chance came when he played Simmons during the British Masters in June. As they played, a "sequence of events" detailed by Mackay in his complaint "led me to the only sensible conclusion: that he was returning a drawn tile to the bag and drawing a new one."

After Mackay lodged his complaint, similar allegations were raised, leading the ABSP to "the natural conclusion ... that he had been cheating," Elie Dangoor, a member of the ABSP, said in a statement to multiple media organizations.

"There's no one person bigger than the game," Dangoor added.

Simmons acknowledged some occasional, slight discrepancies in his play in an interview with the Times, where he wrote a weekly column until the paper noted Monday he would "no longer be a contributor." But Simmons denied cheating.

"You have to remember that at the top level, games can be quite intense and there's a lot going through one's mind let alone remembering to religiously ensure tile drawing rules are followed meticulously," he said. "From the outset I have said that no one is beyond suspicion and complied fully with the investigative process."

The ban, which Simmons has elected not to appeal, and the attention it has received have raised eyebrows in the Scrabble community, The New York Times reports. The paper points out that ASBP Chairwoman Amy Byrne resigned following the ban, and Nicky Huitson, a tournament organizer, explained to the newspaper that "most of us don't want to talk about it."

It doesn't appear that Simmons wants to either. He has so far offered comment only to the Times of London.

"I had actually been winding down the number of tournaments I play anyway with a view to retiring because I was spending far too much time keeping on top of word learning, coupled with long drives to events, and stressful games," he told the British publication.

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