Both Minnesota groups vying for a Major League Soccer expansion franchise can be encouraged by the varying examples of stadiums, or stadium plans, the league has been willing to work with in its expansion drive.

The Vikings can reference Atlanta’s new club, which will play its inaugural 2017 season in a new stadium to be shared with the NFL’s Falcons.

Minnesota United FC can look to a once fellow lower-division club in Orlando City SC, which will move to MLS for the 2015 season and will play in the Citrus Bowl stadium until its new soccer-centric home is ready in 2016.

These divergent, yet both agreeable, examples mean the Vikings and United remain viable options to land an expansion franchise despite their own drastically different stadium situations.

The Vikings, United and a groups from Sacramento, Calif., and Las Vegas presented their cases to the league’s leadership in November. The four groups await a decision on the league awarding an expansion franchise in the first half of 2015.

“If Minnesota is getting it, which I believe it is, stadiums are first and foremost,” said ESPN soccer commentator Taylor Twellman. “There are no ideas of stadiums. There’s no this or that. You need to have a stadium approved, and it needs to be ready to rock for a market like this to work, and it needs to be downtown and next to public transit.”

The Vikings have a concrete plan. A $1 billion, indoor stadium in downtown Minneapolis is being built and would be ready for soccer in 2017. The new MLS club would play on field turf in a 65,000-seat building that would incorporate a “house-reduction mechanism” to bring capacity to about 25,000.

United has nascent plans to build a new stadium. The Loons play their North American Soccer League matches at the National Sports Center in Blaine, and one possible plan is an 18,000-seat, natural-grass, outdoor stadium adjacent to Target Field in downtown Minneapolis.

United has not disclosed whether they would seek public financing to help pay for a new stadium. Land acquisition is not considered to be a problem.

Minneapolis City Council President Barb Johnson previously told the Pioneer Press she didn’t believe there would be a civic interest in committing public monies to another stadium.

While there are encouraging stories about expansion plans fitting both the Vikings and United situations, there also are cautionary tales.

New York City FC will play its first season in 2015 in Yankee Stadium next season as new stadium plans and locations still are being worked out.

In Miami, many difficulties in securing a stadium site have hindered prospects of MLS placing a franchise in South Florida for a second time.

Twellman referenced the “struggles” in New York and “debacle” in Miami before making his point about the importance of having stadium solutions figured out.

If the Vikings receive the club, they would join a minority of MLS teams that play in multi-purpose stadiums. Of the 20 MLS teams to play next season, six will play in larger, often-shared stadiums.

Existing examples include: the Seattle Sounders at CenturyLink Field with the NFL’s Seahawks; the New England Revolution at Gillette Stadium with the NFL’s Patriots; and the Vancouver Whitecaps at BC Place with the Canadian Football League’s Lions.

If United receives the club, they would join the majority of 14 MLS teams that will play in soccer-centric stadiums next season.

Soccer’s preferred playing surface is grass, and 15 MLS teams have a natural surface as their home base.

“I hate turf. I hated playing on it,” said Twellman, a Minnesota-born player who played in MLS and for the U.S. men’s national team.

When the International Champions Cup was played at TCF Bank Stadium in August, grass sod was temporarily laid over the artificial field turf for a match between elite international clubs Manchester City and Olympiacos.

“However, something has changed over the last few years,” Twellman said.

While FIFA, the world’s governing soccer body, has been critical of field turf in Seattle, Twellman said current players have been increasingly satisfied with the modifications made to the artificial surface at the Portland Timbers’ home field.

“As a purist, you want natural grass,” Twellman said. “Who knows? There could be a contingency.”

The Vikings hope so. While the turf might not be Exhibit A, the Vikings often reference Seattle as a leading example of the possible successes within a multi-purpose stadium. The Sounders are the MLS attendance pace-setter with figures sometimes in excess of 50,000 fans.

HKS Sports and Entertainment Group is the architect of the Vikings stadium, while Generator Studio was brought on to enhance the fan experience for MLS about a year ago.

“HKS is designing it as a multipurpose venue, and, of course, the Vikings and then MLS soccer is a key part of that design, so you can play soccer, football and have a variety of other events in there,” said Tom Proebstle, partner at Generator Studio.

Proebstle helped with the initial designs of the Seahawks’ and Sounders’ home and sees similarities to the Vikings’ new home.

Before Sounders games, thousands of soccer supporters march to CenturyLink Field. And a park to the western side of the new Vikings stadium could provide similar opportunities, Proebstle said.

“One of them could be a parade that can start in the park and people can gather there, and at a point, it could head towards the (95-foot) massive doors that open up into the stadium,” Proebstle said.

An enhancement for MLS could be the ability for fans to “decorate their house” with banners and flags, Proebstle said. Sporting Park, home of MLS club Sporting Kansas City, allows fans to place scarfs of other clubs on a wall within the stadium’s supporters’ bar.

“It’s really giving the supporters and the fans the opportunity to create their own traditions,” said Proebstle, whose work credits include designs for the renovation Green Bay’s Lambeau Field and the construction of the Indiana Pacers’ Bankers Life Fieldhouse. “We are setting a foundation for these things to happen.”

In soccer society, banners and flags are called “tifo,” but those items are just window dressing to critics of multi-purpose stadiums.

“Dual purpose really has to put one sport first,” said Bruce Miller, a senior architect with Populous. “It’s like any other franchise. They want to have a home. They want a tailor-built facility that suits their fans — really to reinforce their brand and their experience and what they have to offer.”

Miller cited two dual-purpose experiences that lacked the intimacy of soccer-centric stadiums: D.C. United games at RFK Stadium and Kansas City Wizards games at Arrowhead Stadium. Both those stadiums are more than double the capacity of soccer-centric stadiums at 18,000 to 22,000.

“I used to go to (Kansas City) games, and it was terrible experience,” said Miller, whose work credits include Target Field. “You would get club-level tickets and would be twice as far away as you are at purpose-built buildings.”

The Kansas City club changed its name and moved into a jewel box in 2011 — its own, 18,000-seat grass-surfaced venue. D.C. United will follow suit into its own, 20,000-seat stadium with a grass pitch in 2017.

Tailored soccer stadiums have seats close to a standard-size pitch (120 yards long and 75 yards wide) while allowing adequate room for corner kicks and benches. The north stands in the Vikings new stadium are able to retract, so they can reach 75 feet wide.

Outdoor stadiums such as Sporting KC’s home and ideas for United’s home include a covering over the stands for protection from inclement weather and to create a megaphone effect for fan noise.

“The European model of an immersed experience is created by a full canopy,” Miller said. “That kind of shell around the seating bowl that still keeps it open enough to allow for natural grass. I think that’s a key feature. It’s like baseball: you want to play outdoors.”

As a native Minnesotan now living in Kansas City, Proebstle contested that outdoor claim. He admitted he’s lost his “edge” in dealing with the cold, saying he has gotten chilly at Sporting KC playoff matches in November.

Proebstle said the Vikings’ stadium’s indoor environment with a translucent roof and an ability to expand its seating capacity with the expected growth of the sport makes it the best fit for MLS.

Yet, given MLS’ expansion ways, it could go in either direction.

Follow Andy Greder at twitter.com/andygreder.