North Carolina Courage's Jessica McDonald, second from left, heads the ball on goal during the team’s NWSL soccer championship game against the Portland Thorns in Portland, Ore., on Sept. 22. (AP file photo)

While record crowds at National Women’s Soccer League games are evidence of a World Cup bump, players want the momentum to extend beyond the ticket office.

Portland drew a league-record 25,218 fans to a game against the defending champion North Carolina Courage earlier this month, and last weekend Sky Blue staged its first game at Red Bull Arena before a club-high 9,415 fans. The Chicago Red Stars had to open the upper-deck section at SeatGeek Stadium when they drew more than 17,000 to a post-World Cup game.

Across the league, attendance is up about 15% overall this year, with the most dramatic swings coming after the United States’ victory this summer at the Women’s World Cup in France. That’s the bump: Both the NWSL and its male counterpart, Major League Soccer, traditionally see increased interest during a World Cup year.

In the NWSL, the bump is likely to be larger once the entire season plays out. In 2015, following the national team’s World Cup victory in Canada, the league drew an average of 5,046 fans per game, up from the league’s all-time low average attendance (4,137) in 2014. Following last weekend’s games, average attendance across the league was 6,917.

But players aren’t satisfied. In addition to bringing in new fans, they want sustained growth and stability.

The key is investment.

“We’ve won two World Cups back-to-back. We’ve done everything on the field to encourage and inspire players and kids and parents and coaches, boys and girls to come to the games,” said Carli Lloyd, who plays for Sky Blue and is a member of the U.S. team. “Now again it’s up to the people with money to market it, to buy into this, to invest in it, and to promote it.”

While the NWSL has been incrementally drawing bigger crowds since its inception in 2013, there have been recent questions about the league’s health.