- The NFL returned to London for first of two games at Wembley Stadium this season
- Minnesota Vikings defeated Pittsburgh Steelers 34-27 in thrilling game
- NFL organizers want to continue to invest in European games
- But fans and experts alike warn there are many logistical problems still to be resolved
Viking raiders once landed on British soil to change the face of the nation -- and 1200 years later a group of muscly Minnesota Vikings gained further ground in the NFL's sporting invasion of the British Isles.
The victorious Vikings landed another blow for American football Sunday as the team staged an exciting 34-27 victory over the Pittsburgh Steelers in London.
The team's 28-year-old star running back Adrian Peterson and Greg Jennings scored two touchdowns apiece.
It was an important first win of the season for the Vikings but the entertaining game could have even greater significance for the NFL's hopes of establishing a European franchise.
A regular season game was first played in London in 2007 but, for the first time this season, two games were scheduled on the opposite side of the Atlantic.
Next month the Jackonsonville Jaguars face the San Francisco 49ers. Both NFL games at Wembley Stadium sold out within hours.
Organizers of the NFL's London foray stirred the fever further Saturday as they held a block party for an estimated half a million fans on the streets of central London
"It is a sign that the game is growing globally," NFL commissioner Roger Goodell told NFLUK.com earlier this year.
"I think the message is clear. There are passionate fans who love the NFL in the UK."
There were also plenty of domestic fans who were happy to travel to London to support their teams.
"I love it," Richard from Pittsburgh, who now lives in Hollywood, told CNN. "It's a really good idea.
"It gets the Steelers brand out there internationally as a big team."
Dan from New York added: "I love the pub atmosphere in London. Although American culture is the tailgate, which I'm not seeing here!"
Perhaps not every facet of the American football experience can so easily translate to British shores where soccer, rugby and cricket hold sway as the most popular spectator sports.
But that is not deterring the NFL from pressing on with its mission to gain new ground in Europe.
American football is just that, an American sport, but if the sport can successfully "go global" that presents the NFL with new markets and new business opportunities.
Profit not a priority
"This is an investment and we are trying to grow something," Alistair Kirkwood, managing director of NFL UK, told CNN. "We are not concerned about profit yet.
"But for the last two years our games have broken merchandise records for Wembley for all events -- and that includes pop concerts."
Developing the NFL in London, or any European franchise for that matter, does not come without its problems.
"There are multiple challenges," USA Today's NFL writer Tom Pelissero, who was at the game in London, explained to CNN.
"Travel would scare off a lot of potential free agents, it could be hard for a team to be competitive just because of that.
"The tax [in the UK] is another issue, 45% is the top tax bracket. That is something that, again, could scare off players from coming over.
"It also comes down to the fan base being large enough. You can fill Wembley with 80,000 people once, twice this year, but can you do that for 10 games a year? I think that's the one of the many unknowns.
"If you put a team in London, I don't think it would be difficult to make a profit.
"But what do you do when [they] have to play 10 games in the United States? How do you get them to travel? Do any of the visiting fans travel at all? That's an entirely different sort of issue."
Steve, who made the journey from London to New York, was also skeptical about the reality that NFL could become a regular fixture in London.
"The time zones and travel present a serious issue," he told CNN.
"To have a global sport that's weekly is troublesome. If you break it up into something that is less frequent than weekly and that allows for serious travel then it makes sense.
"[A London franchise] is a great idea, the NFL would make a ton of money out of it. I just haven't figured out how it could work!"
The man in charge of the game, Commissioner Goodell, is also juggling the numbers to work out how to develop the game away from north American shores.
"What is the next step? Do we move to three games, are there other ways to grow the game in the UK?" he said. "This is a market where we need to be more active and to grow our game."
For now, Peterson -- who had never been outside the U.S. before his trip to London -- and his fellow Viking raiders can feel satisfied with winning the game, as well as perhaps inching the NFL a little closer to a permanent place on sport's European map.