These are heady times for rugby union in the United States. With a first victory over a Tier One country courtesy of a 30-29 win against Scotland and with qualification secured for next year's Rugby World Cup in Japan, the sport is riding an unprecedented wave of success.

Maintaining momentum will be a major challenge for everyone involved in the sport in the U.S., most notably Dean Howes, commissioner of Major League Rugby. The competition reaches its inaugural semifinal-playoffs Saturday and with the matches being televised domestically, the early signs are that after the damaging demise of PRO Rugby in 2016, rugby union in the U.S. really is starting to change perceptions at home and abroad.

"That is one of the main goals of the MLR," said Howes, who is understandably upbeat having worked so hard to get MLR off the ground. "We have seen a real improvement leading up the semifinals. Attendances are growing every week but we understand we have to become relevant to sports fans and with more time next year to sell season tickets, things will be even better."

Breaking the U.S. market is a tantalising prospect for rugby union, given the number of outstanding athletes who do not make it in American Football but possess running and handling skills that could be transferred.

Of course, international success helps the cause and the U.S. Eagles' win over Scotland quickly followed by victory over Canada created headlines and highlights reels to be broadcast across the nation. Participation in the World Cup, where the U.S. will face England, France, Argentina and Tonga, added to the sevens team's triumph in the HSBC World Rugby Sevens Series event in Las Vegas in March, are more encouraging signs.

"By having MLR we are enabling players to move into the elite level of the game to represent the U.S. Eagles and be more competitive internationally," said Howes.

"12 months ago, I was convinced we had the right template but that didn't mean it would guarantee success. We have a lot of work to do getting the right professional facilities and the player pool but I was comfortable that with the owners at the table it would work."

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On Saturday, the Seattle Seawolves take on the San Diego Legion before the Glendale Raptors face the Utah Warriors, with both semifinals hosted at Infinity Park in Glendale, Colorado. "It is going to be an exciting day for MLR," Howes adds.

And with the first season of MLR drawing to a close, the American is eager to push ahead with expansion plans safe in the knowledge that the World Cup is going to raise the profile of the sport through their TV deals with CBS Sports Network, ESPN and AT&T SportsNet.

The current MLR comprises the four semifinalists plus the Austin Elite, the New Orleans Gold and the Houston Sabercats. Expansion is planned to take the league to nine or 10 clubs in 2019 with Dallas [where ex-Bath director of rugby Mike Ford is in charge], New York, Los Angeles, Washington, Boston and Ontario all keen to get on board.

The financial position of the USA Rugby governing body is currently under review and with PRO Rugby having folded, there is understandable need for MLR to get its sums right. Howes is convinced that previous mistakes can be avoided.

"Our goal is to have a five to seven-year plan that will mean the MLR will continue long after I am gone," he explained. "The 2019 World Cup will focus attention on rugby and hopefully the US Eagles players will be identified with their MLR teams -- and that is an exciting development."