By ANNE M. PETERSON, AP Sports Writer

PORTLAND, Ore. (AP) — Nowhere could the World Cup bump in women's soccer be more apparent than in Portland, Oregon, where more than 21,000 fans watched a National Women's Soccer League rivalry match between the Thorns and the Seattle Reign.

It was the second-largest stand-alone crowd ever to watch a professional women's league game in the United States. And while soccer-crazy Portland usually attracts big crowds for the hometown Thorns, the rest of the league is also seeing a surge in interest.

The NWSL is loving the attention.

"The last few weeks have been really, really nice for all of us," NWSL Commissioner Jeff Plush said. "But there's more hard work. It continues to be a business we work very hard at every day. So it's not going to be a panacea. You have to work hard at growth."

The U.S. women's national team, whose players are allocated throughout the NWSL, defeated Japan 5-2 earlier this month in the title match at the World Cup, which was played across six Canadian cities. It was the team's third World Cup title, most of any nation.

The players have since returned to their club teams and to crowds eager to see the American victors.

The NWSL is in its third season and is in a crucial period because no other women's league in the United States has been able to last very long. Both forerunners, the Women's United Soccer Association (WUSA) and Women's Professional Soccer (WPS) each folded within the three-year mark.

The league has attracted major sponsors, including Nike and, this season, Coppertone. In late June, the NWSL and FOX Sports announced an agreement to broadcast 10 league games this season. Three regular-season matches, three playoff matches and the championship will be shown on FOX Sports 1.

But it's the fans that have been making a difference in the past couple of weeks.

The Thorns set the league's attendance record on Wednesday night with a sellout crowd of 21,144 for a match against the rival Seattle Reign at Providence Park.

The record for a stand-alone professional women's soccer match in the United States was set in 2001, when 34,148 watched the Washington Freedom defeat the Bay Area CyberRays 1-0 at RFK Stadium. Mia Hamm starred for the Freedom while Brandi Chastain led the CyberRays.

While other women's pro matches have drawn more than the Thorns did Wednesday night, those were double-headers held in conjunction with men's games.

The Thorns lead the league in attendance by a wide margin, averaging 13,769 fans a game this season. Wednesday night's match marked the fourth time the crowd has gone over 16,000 at the downtown stadium, which is also home to Major League Soccer's Portland Timbers.

Other teams also have seen a spike in attendance.

The Washington Spirit drew a club record 5,413 fans to Saturday's 3-0 victory over the Reign at the Maryland SoccerPlex. The same day, the Chicago Red Stars played to a 1-1 draw with Boston before a record 3,560 fans at Benedictine University.

A record 13,025 fans turned out at BBVA Compass Stadium in Houston for the Dash match against the Red Stars. U.S. stars Carli Lloyd, Meghan Klingenberg and Morgan Brian were honored but didn't play.

"I think people just totally got attached to this World Cup in a different way than they have and it was so close to home," U.S. midfielder Megan Rapinoe said about the bump. "That was such a huge thing to have American fans know they can go watch these players in their own cities for the rest of the season. Hopefully the bounce isn't coming down, it's just continuing to go up."

The WUSA was founded in 2000, hoping to capitalize on the U.S. national team's victory in the 1999 World Cup, but the league folded in 2003. The WPS played from 2010-2012 but had insurmountable internal organization and financial issues.

The NWSL has always maintained that it is better positioned to succeed because of its association with the North American soccer federations — the United States, Canada and Mexico — which pay the salaries of their national team players to help keep costs down.

Thorns coach Paul Riley said the real benefits of the World Cup probably won't be seen until next year — in season ticket sales.

"We're an anomaly when it comes to that. But you know, with Boston, Chicago, these places that have a huge boost right now, can they deliver season tickets? I know all the teams are working hard to get it done," Riley said. "Our job is to entertain. Our job is to put teams out that people want to come pay money to watch, and put them in suitable stadiums for people to watch. I think that's the next step for everybody and hopefully they can do that, the whole league."

Plush agreed there's more work ahead. The league, which right now has nine teams, could expand, possibly even next season.

The NWSL could also get another bump next season from the 2016 Olympics.

"The health of the league is good. It's exactly where we expected to be and where we wanted to be in the third year," Plush said. "I think it's important for people to understand the context as a startup business. We're 2½ years in. Certainly the product is compelling, but we have the challenges and issues any business has. That said, we are rigorously planning for Year 4 and we have all the confidence in Year 5 and Year 6."