West Ham United were visited by two of world's biggest football stars recently, but the vast majority of fans did not even know they were here!

Indianapolis Colts quarterback Andrew Luck and tight end Coby Fleener were guests of the Hammers for the Barclays Premier League fixture with Liverpool. American footballers Luck, who stands 6'4", and close friend and former Stanford University team-mate Fleener, 6'6", are both enthusiastic fans of what Americans commonly call soccer.

Luck, who spent part of his childhood living in west London, and Fleener thoroughly enjoyed their first visit to the Boleyn Ground, asking countless questions about the team, the history of the Club and the Hammers' upcoming move to the Olympic Stadium.

WATCH ANDREW LUCK AND COBY FLEENER ON WEST HAM TV!

"I love soccer, or I will try to refer it as football!" smiled the 24-year-old quarterback, who was the No1 pick in the 2012 NFL draft and has led the Colts to the Play-Offs in each of his first two seasons as a professional.

"I love playing it and love watching it and it's definitely getting a lot of popularity in the States as well. I have been to a bunch of MLS games and watched Robbie Keane and David Beckham play, but it's nice to be over here and be a fan. It's fun for us to play [American football] but it's also fun for us to watch and be fans of sports.

"My Dad was working over here for the NFL and growing up I remember going to Arsenal and Crystal Palace games, but this is my first trip out to West Ham, so we're very excited and happy that you had us to visit."

Aside from living in London, Luck also spent part of his upbringing in Texas, where he father served as President and General Manager of the MLS franchise Houston Dynamo.

While Illinois native Fleener has no historical links with soccer like his friend, the 25-year-old has quickly been educated in the nuances of the sport by Luck.

"Andrew has definitely been the driving force behind my love of the game," said Fleener. "He has shown me the way as to how to be a fan and this is my first time out here to watch a game, so I'm excited!"

While American football has big hits, touchdowns and timeouts, soccer is a continuous, fast-flowing game with fewer goals - or points - scored, so what do the two NFL giants like so much about the beautiful game?

Andrew Luck Coby Fleener

"For me, I'm interested in seeing fans because they are so passionate about their team, their home base and where they are from," Fleener revealed. "That, to me, is the most exciting thing about soccer.

"I catch games in the States every once in a while. As Andrew said, the sport is growing in popularity so with football and 'football' together, there is always something on TV."

Neither player has a favourite team, with Luck instead choosing to follow the American players in the Barclays Premier League, but Fleener admitted he could well become a Hammer.

"I think there's a good chance of that happening, absolutely!" confirmed the No80.

While the Barclays Premier League season is approaching its conclusion, Luck and Fleener and their fellow American footballers are currently resting their bodies ahead of the start of the 2014 NFL season in early September.

The Colts have reached the Play-Offs in eleven of the previous 12 years, defeating the Chicago Bears in Super Bowl XLI in 2006 and losing to the New Orleans Saints in Super Bowl XLIV in 2009. Both of those games were played prior to Luck and Fleener's arrival in Indianapolis, however, and the pair are now eager to write their own names into the Colts illustrious history books.

"Hopefully we're going to win a Super Bowl!" said Luck, who was in London to host a Skills Camp at The Soccerdome in North Greenwich. "We hope to improve and I think we have great pieces, with a bunch of great young players and some veteran leadership.

"We hope this can be our year, but every team is saying the same thing in the off-season."

As a tight end, Fleener fulfils one of the few positions on the offense where he can both defend as a blocker and attack by catching passes thrown by his quarterback - a bit like a central midfielder in soccer.

He knows he has an important role to play if the Colts are to match Luck's ambition by winning Super Bowl XLIX in February 2015.

"It's always my goal to be the No1 tight end, but more importantly for me it's about winning for the team, for the organisation and for the fans back home.

"Just as the West Ham players give their all for the fans around them, that's the same for what we try to do for the Colts. There's always a chance for us to win the Super Bowl, but there is a lot of work to be done before we know if that's going to be an option for us."

*To watch Luck and Fleener's full West Ham TV interview, click here.