A big bettor went undefeated, running from Las Vegas sportsbook to sportsbook, placing multiple six-figure wagers with little regard for the odds. A furniture salesman from Houston hedged a promotion that would cost him $10 million in refunds with big bets on the Houston Astros. And ticket brokers attempted to lay off the risk of losing millions of dollars in potential profits, if the series didn't reach Game 7.

Big money was everywhere in one of the craziest World Series from a gambling perspective that Las Vegas has ever seen.

Night after night, game after game, Las Vegas bookmakers loved their position on what turned out to be the most heavily-bet World Series ever. With all the large bets floating around, they were able to adjust the odds to attract money on whatever side they needed. They had the best of it, at least they thought.

"I had myself in some really terrific spots, just great, great positions," Johnny Avello, executive director of the Wynn race and sports, told ESPN on Thursday afternoon. "Unfortunately, I didn't win any of them."

Official numbers won't be released until the end of the month, but it's safe to say that tens of millions of dollars were wagered on the World Series at Nevada sportsbooks -- a lot of it by one unnamed bettor who went on a weeklong run that will go down in Las Vegas lore.

'Bettor X' wins over $10 million

Sportsbook directors don't make a habit of identifying their customers, and the name of the guy betting big on the World Series was not discussed. But everyone around town was talking about what he did to them.

Sportsbook operator CG Technology, MGM Resorts, South Point, Station Casinos, Westgate SuperBook, William Hill and Wynn each reported taking large bets from the same bettor, referred to by some as "Bettor X."

Casinos ran background checks on Bettor X and found no concerns. He was in his 30s and respected for his UFC action, but he had not regularly bet baseball in the past. According to a source familiar with his betting history, he won 11 straight bets on UFC from late September through the first weekend of October at one sportsbook. It was just the beginning of his run.

The larger bets, peaking in the upper six figures, began with the World Series. He bet on Games 1, 2, 3, 4 and 6, increasing the size of his bets after each game.

He won them all.

At some books, he simply handed back his winning ticket from the previous game, letting it all ride on the next game. Most books allowed him to bet only a certain amount before moving the odds. For example, at one shop he backed the Los Angeles Dodgers in Game 4 at odds of +110, +105, even money, -105 and -110 for a total risk of just over $400,000.

"He just wanted to get down on certain games," Avello said. "He didn't care what the number was. He just wanted to get down. And he just didn't lose."

"The market price would be -110," Jason Simbal, vice president of risk at CG Technology, said, "and the guy would be laying -140." Bettor X's largest wagers were reportedly as much as $800,000 and came on Game 6. Sources around town believe he got down for more than $3 million on the Dodgers in Game 6 -- and he wanted more.

"We have thresholds that we're willing to take risk to," Simbal said. "We have a general idea about how much money we'll be able to get back on the other side, so we were giving him as much as we could to get us to that number."

More than $1 million was bet on Game 6 at CG Technology alone, more than double the amount of money that was bet on Game 7 of the Cubs-Indians World Series. The Dodgers won Game 6 by a score of 3-1.

When it was over, sources familiar with the bettor's action estimated that he took Las Vegas for more than $10 million from Oct. 24 to Oct. 31. "I remember guys going on runs before," said Avello, "but not to this extent."

A mattress promotion gone wrong

It was a big purchase: a $13,000 Tempur-Pedic, split king, adjustable, massaging mattress. But Barry McFadden, a Houston attorney, saw value in it. It was a good bet.

McFadden purchased the mattress from Gallery Furniture right before Game 7 of the American League Championship Series between his Houston Astros and the New York Yankees. The furniture store, owned by Jim "Mattress Mack" McIngvale, was offering to refund any mattress purchases over $3,000, if the Astros won the World Series.

"It's one of the most expensive purchases I've ever made," McFadden, a long-suffering Astros fan, told ESPN. "But I figured I was getting outstanding value, given that it was basically a $13,000 free play, since I was going to buy it anyway.

"Plus, [McIngvale's] efforts after Harvey were just unbelievable," added McFadden, the founder of Houston firm Greathouse Holloway McFadden PLLC. "So we decided to buy one from him, because of everything he's done."

McFadden is an experienced sports bettor and two years ago finished third in the prestigious Westgate Las Vegas SuperContest. He considered flying out to Las Vegas and placing around a $5,000 bet on the Dodgers to at least get the mattress at half price but ultimately decided to stand pat.

Asked how he slept after the Astros' Game 7 victory, McFadden said, "Fantastic."

The Astros' victory will cause $10 million worth of refunds at Gallery Furniture, according to McIngvale, who unlike McFadden decided to hedge his risk in Las Vegas.

In October, just days before the World Series, the respected Houston business mogul placed more than $1 million of bets on the Astros at "four or five" Las Vegas sportsbooks.

"They're not wagers; they're hedges," McIngvale told ESPN.

Sources told ESPN that Caesars Palace and CG Technology were among the shops that took money from McIngvale's action and that his bets were in mid-six-figure range.

"Some of them were small [casinos], some were big," McIngvale said Thursday morning. "Some of them have a little more play in them than others."

McIngvale is giving a speech at an event in California in the coming weeks and said he planned to stop in Las Vegas to collect his winnings. He'll return in December to host a refund party at the store.

"I'm just so happy for the city and for the Astros," McIngvale said. "After the hurricane, we needed this."

A record World Series handle

More money was bet on Astros-Dodgers than any other World Series that Avello has ever booked during his 30-plus-year Las Vegas career.

At William Hill's Nevada sportsbooks, the money bet on this year's World Series was triple the amount that was wagered on the 2016 World Series. The handle was massive, and so were the books' losses.

When asked to discuss how his book did on the World Series, Simbal quipped, "Do we have to?"

CG Technology suffered six-figure losses on Games 1, 2, 3, 4, 5 and 6. On the entire series, multiple sportsbooks said their losses reached into the millions of dollars.

"It was an ugly, ugly World Series," Avello said.