First came talk of labor unrest when Major League Soccer’s collective bargaining agreement expires next year. Then a corporate shake up at United Soccer Leagues. Now a report that a new professional soccer league might be formed to compete with USL and MLS alike next season. These developments, all within the last few months, threaten to shake U.S. professional soccer to its core.

We’ve been here before. The history of professional soccer in this country has been dogged by infighting and mismanagement. The North American Soccer League famously went defunct in 1984, but it was not the first U.S. pro league to do so. Disputes with the U.S. Soccer Federation are said to have caused the demise of the first American Soccer League in 1929, ending a first “golden era” for the sport in this country.

On the surface, all is still well with MLS. By all reports, the league is on solid financial footing. A report by Forbes.com last year found that while MLS was not yet profitable, several teams were in the black with healthy revenue streams league-wide. The cash crunch that nearly doomed MLS early this decade is a distant memory.

But the league is far from in the clear. TV viewership and attendance have gone nowhere the last three years, according to Sports Business Journal. Interestingly enough, this development comes as Americans’ interest in soccer is at an all-time high, as evidenced by Nielsen ratings for World Cup qualifiers and English Premier League games. MLS’ two-year old contract with ESPN doesn’t expire until 2014, but its deal with Fox Soccer Channel ends after 2010–the same year as its collective bargaining agreement with the players’ union.

The CBA expires Jan. 31, to be precise. Negotiations are said to be in the preliminary stage. It is unclear how much leverage, if any, the players have at this juncture. But the new league, should it happen, could give them an intriguing option should there be a work stoppage.

For MLS to survive and prosper, changes are necessary. First off, it needs to pay its players a living wage. The $34,000 minimum salary for senior roster spots is bad enough, but many MLS rosters (indeed, starting lineups) are occupied by developmental players earning $1,175 per month. This dichotomy was well-illustrated in The Beckham Experiment, the recent book by Sports Illustrated writer Grant Wahl (reviewed here). MLS squads compare to third world social economies (tiny, all-dominant upper class, sizeable lower class, no middle class to speak of). Many players are essentially semi-pros, forced to hold down second jobs and keep roommates. The youth academy system needs to change as well; MLS teams develop players they then risk losing to other squads for little or no compensation.

MLS’ single ownership structure, where all teams are controlled by the league, has created a system of parity that essentially gives each club an equal shot at winning championships. But it also prevents any real dynasty from developing. One could argue that a big market villain archetype is exactly what MLS needs to raise awareness with an apathetic U.S. market and to capture more television eyeballs. Without it, MLS matchups lack any of the good guy vs. bad guy narratives of other sports leagues. There are no real favorites in MLS matches–and no real underdogs. Home field advantage and other factors might increase the chances for one side or the other, but mostly every game (and playoff match-up) is a blank slate.

It is perhaps in part for these reasons that a dissident group of owners is threatening to split away from USL, the de-facto “minor league” that grew out of a regional indoor league two decades ago. On Aug. 27, Nike Inc., which inherited the USL structure when it acquired Umbro in 2007, sold the league to NuRock Soccer Holdings LLC. The new owners, no doubt married to the MLS-style single-entity structure that also governed USL, were met with opposition from owners of eight teams wishing to switch to individual team control. Billing themselves the Team Owners Association, the group includes the Atlanta Silverbacks, Carolina RailHawks, Miami FC, Minnesota Thunder, Montreal Impact, St. Louis Soccer United, Tampa Bay Rowdies and Vancouver Whitecaps. Their Aug. 31 statement reads in part:

The TOA believes that this [single entity] ownership structure has stunted the growth and recognition of both the league and its teams during USL’s nearly 25-year existence. Consequently, over the past several years, the TOA has engaged in discussions with the owners of USL to restructure USL and is therefore extremely disappointed with Nike’s decision to sell USL to a non-USL-1 team owner. Accordingly, the TOA now reconfirms its commitment to achieving a team-owner controlled league and will pursue all avenues to do so.

Undermining this struggle is some bad blood between MLS and USL, born of MLS’ nascent habit of expanding into cities where USL has successfully grown roots. In Seattle and Portland, MLS is effectively taking an existing fanbase and infrastructure (and often team name and colors) and converting these to Major League Soccer franchises. No surprise then, that the TOA includes clubs in cities without an MLS presence (Vancouver will join MLS in 2011 and the existing ownership appears determined to not let its identity be usurped by an expansion franchise). And no surprise, either, that TOA spokesman, Carolina Railhawks majority owner Selby Welman, also identified the USL-2 New York City franchise as a club he would like to have on board. MLS has famously not made many inroads in the country’s largest market.

Whatever its form, it appears a team-controlled professional league is only a matter of time. Whether the new owners agree to turn USL into the structure the TOA is pursuing, or if the dissident teams decide to go it on their own, we can expect to see some form of individual team ownership soon, probably as early as 2010. What happens then is anybody’s guess. If there is a work stoppage in MLS, this league could quickly gain traction. With international investors (big-name European clubs are all but chomping at the bit to buy into U.S. soccer franchises) pumping in cash, it could finally put U.S. club soccer on the map. Or the whole thing could collapse under its own weight (see NASL). Or any number of myriad possibilities. But don’t be surprised if one year from now the professional soccer landscape in the U.S. is completely different from the one we have today.