BALTIMORE — He is adamant there will be a banner hanging from the rafters, that he will commission championship rings, that the celebration had to include T-shirts and hats and “We Are The Champions” playing in the background.

The Foster Trophy will be displayed prominently inside Capital One Arena. The names of the players who won this title will go down in franchise lore, never mind if most Washington sports fans can’t name them.

The Washington Valor won the 2018 Arena Bowl — after a 2-10 regular season — advancing through a four-team playoff bracket that included all four Arena Football League franchises. Ted Leonsis isn’t apologizing for any of it.

He still believes arena football will become one of the cornerstones of the next era of his sports business holdings. That his properties will be a family-friendly “hothouse” of legal gambling and play-by-play fantasy sports. That data and analytics will be harnessed to provide instant content tailored to individual fans.

To arrive there, Leonsis, 61, is in the midst of a takeover of the Arena Football League, an organization that’s spent nearly a decade on the brink of collapse.

At its height in 2007, the league boasted 19 teams in cities including Grand Rapids, Mich., and Austin. Two years later it shriveled. There was no 2009 season. After Leonsis introduced the Valor and Brigade in 2017, he also emerged as the league’s greatest booster. And, seeing that he has the money and the vision, the league plays by his rules.

“If we didn’t step in,” he said, “it probably would have died.”

The league adopted his suggestion for a new playoff format: a two-game, home-and-home series with the winner advancing based on aggregate scoring. It installed Randall Boe, Monumental’s general counsel and Leonsis’ colleague dating back to their days as AOL executives, as its new commissioner.

Leonsis recruits prospective franchise owners. He hosted Tom Kartsotis, founder of watch company Shinola Detroit, as a personal guest at the Arena Bowl with the hopes of expanding the league to Motor City.

He’s trying to convince Philadelphia franchise owners to start a second team in Atlantic City; trying to get Dan Gilbert, owner of the NBA’s Cavaliers and AFL’s Gladiators, to play through arena renovations; considering buying another franchise himself to put in Richmond.

“When he said, ‘Let’s do two teams,’ we chuckled a little bit,” said Zachary Leonsis, his son and a senior vice president at Monumental, “then said, ‘Let’s go for it.’”

Even owning a third team wouldn’t be much of a gamble for Leonsis, whose net worth Forbes estimates is around $1.1 billion. But since buying the teams, he’s been the subject of questions varying on the theme, “What is Ted doing?”

He’s eager to tell you, eager enough that he’s three times sketched out his vision on his blog.

“I firmly believe indoor sports are ascending,” he wrote in one blog post, a line he repeated three times in interviews for this story.

He can control the environment indoors. There are no rainouts. Fans never have to sit out in the cold or under a blazing sun. A good sports arena is like a casino: there are so many sounds and flashing lights and fun things to look at, it makes you forget what day of the week it is.

America needs more indoor sports, Leonsis thinks. He twice almost purchased D.C. United — for a good price, too, he added — but passed.

“It’s outdoors,” he said, “and you know, that’s just not what I think will work.”

He wants an event with constant action. That’s why he’s drawn to hockey and basketball and even esports; players go up and down the court or rink or map mostly without stoppages.

They are games, he said, that appeal to younger audiences. Viewers can catch a glimpse of a contest and still see scoring or highlight-worthy plays. With that much energy, they’re hard to look away from.

And arena football, he said, has the same quality. The clock runs continuously. Huddles take a fraction of the time as they do in the NFL. Quarterbacks have less time in the pocket to throw the ball. The field is so small, only 50 yards, that teams can (and regularly do) score from anywhere on any given play.

Leonsis calls arena football “the esports of football.” He hopes the tempo, the scoring, the ticket prices are more attractive to a younger audience.

“Which of these games,” he asked, “the AFL or the NFL, most reminds you of esports and has relevance to young people? Hands down, you would say the Arena Football League.”

And by taking control of the league now, Leonsis wants to shape its future content, creating a multiscreen experience similar to how NFL fans watch games on TV while checking fantasy football scores on their phones. The arena league can fashion the data that powers fantasy football into more gaming options, including gambling.

“Gaming and gambling and wagering are the promised land for media and sports,” Leonsis said.

He envisions games where fans can gamble — on whether the next play will be a run or pass, whether a quarterback completes his next attempt, the score at the end of quarters — and use reams of data generated from past regular season games to make informed decisions.

That will inform the league’s new media rights deal. Under its soon-expiring agreement with CBS Sports, the AFL paid the network to broadcast its games.

“There’s appetite out there,” he said. “Amazon and Netflix, Facebook, Apple, they’re all going to move into this. They see the power of sports.”

Leonsis knows the power of sports, too. He owns the team that drew 18,000 people to Capital One Arena to watch a Stanley Cup finals game on a screen, that drew tens of thousands more on the streets outside, that drew hundreds of thousands to watch a parade on a skillet called Constitution Avenue.

There were as many Washington Capitals shirts as there were Valor or Brigade shirts in the Arena Bowl crowd. These were spectators drawn to Leonsis’ latest experiment. They queued up stairs in the bleachers to take pictures with him. They shook hands and said, “Thank you.”

Leonsis walked behind each team’s bench and asked fans how much they paid for their seats ($47) and if they’d been to an AFL game before. Most had not.

“We’re here,” one said mid-handshake, “because you’re here.”

To some degree, so are the players and coaches. So is the rest of the AFL.

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