Last summer, MLS commissioner Don Garber caused a stir by announcing that the league plans to add four new expansion teams by 2020. One of them, in Orlando, has already been announced for the 2015 season, but three are still up in the air - and on Tuesday, Minnesota soccer fans got the clearest indication yet that Minneapolis is on the league's short list.

During Garber's state of the league address ahead of this weekend's MLS final, a slide was displayed with five cities marked as potential expansion destinations: Miami, Atlanta, St. Louis, San Antonio, and Minneapolis. (NOTE: The commissioner said he hadn't seen the slide before the presentation, so make of that what you will.)

You can watch the whole event here, but the commissioner confirmed that the two markets that are farthest along are Miami, which has an expansion bid led by David Beckham but needs to find a stadium to play in, and Atlanta, which is fairly close to finalizing a deal that would land an MLS team in the Falcons' new stadium, which is projected to open in 2017.

The Atlanta/Miami/Orlando triumvirate would fill the Southeastern hole on the current MLS map, but Garber specifically mentioned the Midwest as another hole. According to the league's official website, he said, ""There are a number of other markets that we don’t have teams in that are large swaths of the country... The Midwest is one of them, which is why we’ve thrown Minneapolis out [as a potential destination]. There are a number of cities in Texas which are intriguing to us. San Antonio is one, Austin is another... St. Louis could be another great market."

The map ignores a number of other potential destinations for MLS, notably Sacramento and Detroit. That said, virtually every city of any size in America has at least a small group pushing for an MLS franchise in their town; if every place that wanted an MLS franchise got one, it would be a 75-team league.

A team in the Midwest, whether in Minneapolis, St. Louis, or elsewhere, would help serve as a potential rival with Chicago and Kansas City; the league has leveraged built-in geographical rivalries, especially between Seattle, Portland, and Vancouver, to help drive its growth over the past few years.

The new Vikings stadium might be the most likely destination for a potential expansion team, but the cavernous dimensions of the new field could be a concern. Vancouver, which plays in 54,000-seat BC Place, reduces the size of the stadium for Whitecaps games by stringing white sheets over the field, as a makeshift roof for the stands, thus making their stadium a little more intimate. Renderings of an MLS setup for the new Falcons stadium show a similar system in place.

The Wilfs, the owners of the Vikings, floated the possibility of MLS in Minnesota several times during the stadium negotiations, but have never revealed any serious plans of bringing a franchise to town. It is possible, of course, that those rumors were mostly a canard to help push the stadium through the Legislature, as a partial answer to concerns that the new stadium will be a billion dollars that are being spent on ten Sundays per year.

Minnesota United FC owner Dr. Bill McGuire has insisted that his focus is on operating his team in the NASL, rather than positioning it for a potential MLS expansion bid.

As always with talk of an MLS franchise in Minnesota, many, many questions remain. But it's clear that, in the league's collective mind, Minneapolis remains an intriguing possibility.