The Chicago Bears and Pittsburgh Steelers are two of the oldest and most eminent teams in the NFL. They represent American football in its most romantic sense, harking back to the era when men were men and the game was played as it was meant to be played: in the freezing mud of a mid-western winter.

Both teams are firmly rooted in their communities. At a time when major American sports franchises are hopping from city to city overnight in search of that elusive extra billion dollars, it's impossible to imagine either the Bears or the Steelers striking camp for another town simply because the residents won't pay for a new stadium.

Though they are now huge corporate enterprises, both teams remain largely family dynasties. The Bears were founded by George Halas in 1920, and were among the 12 teams which formed the first professional league that year. The club's president today is Halas' grandson, Mike McCaskey.

The Steelers are the fifth-oldest franchise in the NFL, and their president, Dan Rooney, is the son of their founder, Art Rooney, originally from Newry, Co Down.

Dan Rooney is one of the biggest players on the Irish-American scene and was a cofounder, with Tony O'Reilly, of the International Fund for Ireland (remember, HJ Heinz is based in Pittsburgh). He has been working towards tomorrow evening's kickoff at Croke Park for 10 years.

Both teams go into this contest, the American Bowl, struggling to emerge from difficult transitions. Although the Steelers reached the Super Bowl only two years ago, since then they've been hit badly by "free agency", i.e., some of their best players have jumped ship, including quarterback Neil O'Donnell.

The Bears have, by their standards, struggled throughout the 1990s after a relatively golden era under coach Mike Ditka, including a Super Bowl win in 1986.

This summer, in their attempts to climb out of the doldrums, both the Bears and the Steelers have taken probably the biggest gamble in American football: they're going with new quarterbacks. So unquestionably, tomorrow's most interesting match-up is going to be between the Bears' new boy, Rick Mirer, and the Steelers' versatile Kordell "Slash" Stewart.

Mirer, who had an outstanding collegiate career with Notre Dame, arrived in Chicago after several disappointing seasons with the Seattle Seahawks. For Mirer, it's something of a homecoming: he was reared just across the Indiana border.

"The one thing about the Bears is that there's seven guys from Notre Dame," he says, "so I immediately had friends when I walked in the door. This is a bit different, maybe because of more media exposure, bigger city and having to learn everything quickly to get ready to play."

He's polite about it, but he's delighted to have left Seattle. "It's definitely a situation I have improved on. I thought things could have been better in Seattle, but, possibly, the past year or two, as difficult as it has been, it's been a blessing to create a way for me to get somewhere else. I feel now that I'm surrounded by some great people, a great organisation, and a great opportunity to win".

It does mean having to learn a new playing system. "I'm really enjoying that, because I think this system fits me and I fit this system better than the way we were doing things in Seattle. It just feels like there's a very well-thought-out process with every play we run. We might even have more talent here, and that's encouraging."

You have to wonder, given the enormous pressure he's under in the new job, whether having to make his debut 5,000 miles from home is the ideal start.

"I don't know. I think there's a lot of things that are happening for the first time for me, now, you know. I've never played overseas, I've never played on Monday night - we're going to do that on opening day (akin to the Sky Monday Premiership matches). It's a long trip, if nothing else, and it takes a bit more concentration to keep your mind clear, and we have to get some work done before we have time to do some other things (touring).

"We have to take it seriously, but maybe me especially because I'm learning everything."

For "Slash" Stewart, tomorrow's game is no less important. It's his chance, finally, to nail down the starting quarterback position. Stewart came to the Steelers three years ago from the University of Colorado, where he orchestrated their successful "wishbone" offence, in which the quarterback operates more as a running back than as a strategic passer of the ball.

When he arrived in Pittsburgh he found himself third or fourth back-up to O'Donnell, and so the coaches felt free to gamble with him a bit: they put him in as a running back, as a wide receiver, as a kick return specialist and even, sometimes, as quarterback. When coach Bill Cowher studied the team sheet, he saw: Stewart - RB/WR/RS/QB. Hence, "Slash".

Mister Utility. He revelled in it. "Oh yeah, that was something I never dreamed of doing, and to have fun while I was at it made it exciting. You know, I knew I was going to go out and catch so many balls, and run so many for a first down and throw so many for a touchdown, it was exciting. And it brought a little extracurricular to my game as quarterback.

"I've done some things I never thought I'd be able to do. I'm overwhelmed actually, cause it's given me the opportunity to do tons of marketing things, it's given me the opportunity to even be the starter right now. I don't regret it one bit."

Kordell has just signed a new, four-year contract worth $9 million. There was also a $2.6 million signing bonus. That kind of money has to be earned, and now Kordell hopes to lay Slash to rest.

"Well, you know, I'm still Slash, but yeah, I guess you could say it's a coming out party for me. It'll be my first time having an opportunity to start against a team, and be able to get, I guess you could say, my pants wet far as getting out there and getting some action.

"I've got to prove I deserve the start. There's a thousand guys can go out and play football. Now that I know my position, I know where I am, and it's just a matter of me going out and having fun. It's just a matter of me going out there and being Kordell Stewart as the quarterback, just let things happen.

"I just want to go out and get some things done. It's just a matter of me getting out there and making things happen within the system, and have fun and enjoy myself. And not try to make big things happen, just be very poised and relax and just have fun with my guys out there."

Although the game is the first pre-season outing for both sides, it would be wrong to describe it as a friendly. There is little room for sentiment in American professional sport, and every player is going to be under scrutiny. Both teams are preparing to cut about 30 players from their squads before the start of the season. Livelihoods are on the line.

"What they're going to see is a serious football game," Stewart says. "It's a live football game. But the only thing that's gonna happen differently to regular season games is we're going to have more guys playing. You're going to have the younger guys, the rookies, guys who've been in the league one year, two years. You know, this is the time now for coaches to evaluate who's capable of playing, and who's capable of being a starter when the regular season starts. "It's going to be fun, it's going to be a live game, it's going to be very serious. Obviously we're going to have some plays being called, and we're going to be trying to score some touchdowns and some points."

Any holding back, to avoid injury? He laughs at the innocence of the question. "No, no, it's a live game, it's like a Monday night football game where guys are going to go out running wild, trying to make plays, trying to look good so they can get to be the starter. The coaches won't be telling guys to hold back on the hits."

The American Bowl kicks off tomorrow evening at 6.0. Tickets range from £35 in the centre of the Cusack to £8 on Hill 16 (there are children's discounts on Hill 16 and the Nally Stand), and are available from HMV and other usual outlets.