Tendai Mtawarira was skeptical at first. He’s one of the world’s best rugby players, the size of a vending machine with the agility of a running back. He commands such respect that, when he carries the ball, crowds across continents roar his nickname: “Beast!” He heard it in Japan in November as he helped South Africa to its third title at the World Cup.

But earlier this month Mtawarira was in Washington, meeting with a team that had never played a game, in a country that considers rugby a niche sport, finalizing a contract worth a fraction of what he could make elsewhere. Two local business executives had brought him to the nation’s capital in hopes that someone of his stature could help propel the sport into the spotlight in the United States.

Mtawarira told them he would like to give it a try. The South African superstar signed Saturday with Washington’s new Major League Rugby franchise, Old Glory.

Mtawarira says he wants to be an ambassador for the sport in the Washington area.

“I want to go to a place where I can make a meaningful impact, and from what I heard, there’s a lot of African American kids in D.C.,” Mtawarira said in an interview. “I want to come out and be a role model and teach them a lot about my game.”

This signing was, in a way, the result of U.S. rugby’s comeback from the dead. Football effectively relegated the once-popular game to cult status until 2009, when the International Olympic Committee announced it would return to the Olympic Games. This sparked a sharp increase in rugby participation, attendance and viewership, big enough that in 2018 Major League Rugby began its inaugural season with seven teams and a television partnership with CBS Sports Network.

Now, with the league’s third season beginning Feb. 8, Old Glory has signed the biggest star to hit the United States in hopes it will grab attention here while legitimizing the league globally.

“This is a huge deal,” said Chris Dunlavey, a co-owner of the franchise. “We think it’s a game-changer for our league.”

Major League Rugby has a roughly $500,000 salary cap per team to fill out a roster of 30 to 40 players, and Old Glory co-owner Paul Sheehy compared the league’s economics to professional lacrosse — though rugby proponents believe lacrosse will hit a ceiling in North America while rugby’s international popularity gives it a much greater upside. This potential, combined with a rare overlap of events for U.S. rugby — the World Cup, the Major League Rugby regular season and the 2020 Summer Olympics all within a year — left Sheehy with a sense of urgency.

“We’re at a critical juncture for U.S. rugby,” Sheehy said. “This is rugby’s opportunity to get out of the niche sports and get into the mainstream.”

Expanding the game’s reach is important for Sheehy, who owns Sheehy Auto Stores, and Dunlavey, president of the D.C. management firm Brailsford & Dunlavey, because this is a passion project. Each a former rugby player, they met at the South African embassy and later discussed the potential for a team after watching South Africa play Wales in front of more than 21,000 at RFK Stadium last summer. They jumped into the league because they believe a sport with the time commitment of soccer (80 minutes) and the physicality of football will attract American sports fans. Dunlavey also says the values of the game are appealing.

“In rugby, there’s no 22-year-old millionaires yelling in the face of a referee,” he said. “The ref is addressed as sir and only addressed by the team captain. There’s a level of respect and civility and decorum that you’re expected to maintain.”

Sheehy said he trusted the D.C. market could support professional rugby because of the area’s international population and the sport’s popularity in local Catholic high schools. Sheehy coached and his three sons played at Gonzaga College High in the District, and Sheehy himself played in a World Cup.

Old Glory ownership pitched this opportunity to Mtawarira. It pointed out that MLR is expanding from nine teams to 12 this season. The league is negotiating to add two more nationally televised games per season, for a total of six, and splitting into East Coast and West Coast divisions.

That appealed to Mtawarira. At 34, he’s earned a lot of money and, after the World Cup win, retired from international competition. He estimated he could have earned more than $800,000 playing for well-established professional leagues in France or England, as his teammates have, but he wanted something different. He wanted — in addition to living abroad and expanding his business interests in security and real estate — to help expand rugby in a market that the rest of the world considers, as Dunlavey put it, “a sleeping giant.”

He signed a one-year contract with Old Glory worth a league-maximum $45,000.

The message “resonated [with] me because, at this point in my career, I want to contribute to rugby becoming a force in the U.S.,” Mtawarira said. “I sacrificed a lot of money … but this will help my legacy.”

The 6-foot, 256-pound Mtawarira won’t transform Old Glory into one of the league favorites, said the team’s coach, Andrew Douglas. Douglas predicted Mtawarira has “at least” two great seasons left in him, but that with a young roster, Old Glory likely won’t be able to topple San Diego or Seattle as the class of the league.

Sheehy believes that for the franchise to prove its viability it must sell out each of its eight home games this season at 3,500-seat Cardinal Stadium on the campus of Catholic University. This is about the size of the other stadiums around the league, which also has teams in New York; Boston; Atlanta; Toronto; Glendale, Colo.; Seattle; San Diego; Salt Lake City; Austin; New Orleans; and Houston.

Mtawarira didn’t think he would like Washington, but the city surprised him. It’s larger than he expected, he said, and he was impressed with its restaurants and apartments. It blended monuments and modernity without becoming “crazy busy” like New York, he said. Everything he liked crystallized in one popular residential neighborhood.

“I went to Dupont Circle,” Mtawarira said, “and I think I fell in love.”