Here's a big reason to keep an eye on the pulse of Women's Professional Soccer: A healthy domestic soccer league has an instant and far-reaching effect on a national team.
The evidence has been seen in men's soccer. Major League Soccer debuted in 1996 and quickly boosted a couple of players, including forward Brian McBride and defender Eddie Pope, into the nucleus of the U.S. national team for years to come. MLS still provides a springboard for late bloomers, such as strikers Brian Ching and Chris Wondolowski.
In women's soccer, the defunct WUSA's biggest success story was midfielder Shannon Boxx, who debuted with the national team in 2003, and remains a cornerstone.
WPS has helped several players start or restart their national team careers. The best example is defender Becky Sauerbrunn, who had little more than a cup of coffee with the national team, then proved her worth while playing every minute of the first two WPS seasons with Washington.
Sauerbrunn's longtime Washington teammate, Lori Lindsey, is an example of a player who managed to stay at a high level in the five years between the WUSA and WPS. She didn't play for the national team during her WUSA career (2002-2003), and made a solitary brief appearance for the USA in 2005. But she stuck with the Washington Freedom in the W-League. She earned her way onto the national team with her WPS play, joining the team for 13 games in 2010, and making the 2011 World Cup roster.
A league is especially important for goalkeepers. Hope Solo and primary backup Nicole Barnhart have taken all the playing time for the USA since 2008, except for one appearance by Jill Loyden. But Loyden and pool players Ashlyn Harris and Alyssa Naeher have been able to stay sharp in WPS games.
"Any time you can get high-level games and keep getting experience," Naeher said. "Every game is a learning experience. There's going to be a good competitive game every weekend."
Naeher, the Golden Glove winner (for best goalkeeper) at the 2008 Under-20 World Cup, finished her college career in 2009 and would have had a tough time catching the eye of U.S. coach Pia Sundhage without a U.S. league.
The same is true for WPS rookie of the year candidate Christen Press, a forward who won the 2010 Hermann Award (best college player) at Stanford but has not yet worked her way into the national team mix. Finishing in the top five in WPS goal scoring this year may change that.
"It's hugely important," Press said. "So many of the American stars are here, so there's a lot to learn."
WPS also has helped players prove their fitness after injuries. Defender Amy LePeilbet, who played several international games in three years after her final college season in 2003, had a long road back from an ACL tear. But her play in WPS showed that she was ready to come back to the U.S. team.
Midfielder Megan Rapinoe, one of the breakout stars of the World Cup, also had ACL injuries as she finished her career at Portland. But she came back strong in WPS.
Meghan Klingenberg, a midfielder who just finished a star career at North Carolina, experienced her first U.S. national team camp before the World Cup. She did not make the final cut, but hopes to continue improving her skills in the WPS and make a future Women's World Cup team.
"We need a league in this country to be able to develop players and keep our high level," Klingenberg said. "The rest of the world, as you can see from the Women's World Cup, is catching up. It was an incredible level this year. I enjoyed watching it so much.
"We need this league to develop players and get the best talent in the world so we can train our players to become the best, so we can challenge for the gold every year."