American Football: Super Bowl Xxxix: Martin Johnson

It had some how never occurred that Martin Johnson was capable of lying under a duvet and watching telly late at night, or even that he had ever been a young boy, but this is what he insists he used to do - and used to be - when the Super Bowl was first broadcast over here in the early 1980s. Funny things happen to Johnson when it comes to American football.

People can see this for themselves tonight when he sits on ITV's panel of experts for Super Bowl XXXIX, holding forth about the sport that has become his passion over the past 20 years. And the chances are he will be the biggest expert in the studio. He will certainly match the others for sheer enthusiasm and boyish excitement.

Which is a little disconcerting. The Johnno that rugby hacks have come to know and love is not like this. He hates talking. At press conferences over the years, his body language has basically dared anyone to ask him a question. And coming away with your dignity intact when you have asked him one - indeed getting anything from him at all - has evolved into a kind of game between him and the hacks. It's one we shall miss come the end of this season when he finally retires from rugby.

It turns out, though, that we have been talking about the wrong sport. If only anyone had asked him which picks he thought his beloved San Francisco 49ers would take in the NFL draft, those press conferences might have gone with a swing. Indeed, this interview ends only because my taxi has been waiting for half an hour and because the train waits for no man. At the end of it, on a bit of a roll, Johnson is last seen heading for the hotel reception, no doubt to ask the receptionist if she reckons the Philadelphia Eagles stand a chance against the New England Patriots tonight.

Poor old rugby might feel jealous that one of her greatest players, to whom she has given the best years of her life, was in love with another sport, but Johnson has reassuring words. 'I'd far prefer to play rugby,' he vows, caressing the aggrieved sport's brow. 'I think it's a better game to play. Christ, I've just played 10 years for England and 16 in first-class rugby. So there isn't an issue there.'

All the same, when the subject of his impending date with the Super Bowl is first breached, he lets fly an involuntary cheer of delight.

Johnson's interest in the game is purely as a fan. He did play as a teenager for the youth team of the Leicester Panthers, his local American football team, but he didn't consider taking it any further. 'I'd never be quick enough. In our sport, you try to get good rugby players and make them into athletes. In the NFL they've got some good athletes who they make into players. How quick you do the 40 [run 40 yards] is the big thing. "What? He does the 40 in 4.2? He's that quick?" They love their stats.'

But, for all their stats, they have set an example to rugby for what a spectator sport can do for its audience. The virtues of athleticism, collision and occasion are ones that the union code is only now properly embracing. 'In the early 1980s, watching Rugby Special versus watching the American football was a no-brainer, wasn't it? American football was from another planet. All these guys running around in helmets, smashing each other.

'Whereas in an English club game in the early 1980s you've got guys slogging around a muddy pitch somewhere in January in front of 1200 spectators. In terms of a spectacle there wasn't a comparison. And in rugby if anything untoward happened on the field they brushed it under the carpet. You watch American football - if someone got hit they would replay it five times. So when I went to play American football it was great training, because we used to learn about tackling and hitting, and they got us to lift weights. The coaching was intense. They'd get American guys over to play for the senior team and they used to coach us. They have a real culture of coaching over there.'

Again, lest rugby should feel its nose out of joint at all this eulogy for another sport, Johnson is realistic and English enough to know that there is a lot to love about the homelier qualities of his own sport. He does not think that it was American football that dragged rugby into the twentieth century, rather that rugby just had to change. And, however much he might have benefited from his time playing American football, he appreciates the loyalty in rugby.

'There are lots of things about NFL that aren't particularly nice. It's a very cut-throat industry. But rugby has lots of the nice things of amateurism about it. The teams are still very much teams. It's difficult to get players to change clubs because it's, "Well, I'll miss the lads." And we should try to hold on to that. Because it will change.'

Cut-throat it may be, but American football operates a welfare policy that is extraordinary in the world's most aggressive free- market economy. Every season, the team who finish with the worst record in the NFL, which is a competition without relegation, have the first pick of the talent from college football; the team with the second-worst record, the second pick; and so on. There is also a salary cap to keep things further in order. The design is to ensure that the League remains competitive from top to bottom. The 32 owners of the teams together own the NFL and are answerable to no other organisation.

There are surely lessons here for football in this country, and also for rugby. In rugby there is at least a salary cap, although there is much talk of raising it, and no doubt further down the line there will be talk of abolishing it altogether. Johnson's own team, Leicester, if they move to the Walkers Stadium and remove one of the restrictions keeping them in check, namely the size of their current stadium, would be itching to use the resultant proceeds on assembling a better squad than everyone else.

'We have the biggest average gate and I think we turn over £12 or £13 million,' he says, 'but you need someone to play, don't you? There's no point in us dominating and spending the money, because that would just lead to what happened in the early days of professionalism with everyone struggling to keep up with a few benefactors. You need stability, which we have in the Premiership now. There was a lot of silliness going around in the late 1990s and it was never going to be sustained.'

But, if there's competitiveness in the top flight of English rugby now, what about the international game? Wouldn't a competitive USA improve the World Cup? Could the rugby world compete with a competitive USA? If America is packed full of people bigger, faster and more powerful than Martin Johnson, it would surely all be over for the rest of us, should that talent ever become mobilised.

'There are a lot of guys who come out of high-school football who don't go on to college, and college guys who don't make it to the NFL - and they never play again. What happens to them all? Rugby would have to get a foothold in American sport. But when I went there in 2001 [to train with the 49ers, courtesy of Observer Sport Monthly ] they were interested in me, and the first thing they'd all say was, "Jesus, you guys do that without any pads or helmets on." But rugby hasn't yet got into every household in this country, let alone over there. There are still millions here who'll say, "I watched the World Cup final. Really good. Didn't understand all of it." If the Rugby World Cup ever took a huge gamble and went to America, it would be interesting to see what they could do with it. It's over quicker, apart from anything else. It's fairly spectacular. But you'd be fighting all the tradition. They watch football, baseball, basketball and ice hockey.'

If Johnson had his way, he also would watch as much American football as he could, but unfortunately his wife, Kay, doesn't like it, and there is three-year-old Molly to attend to as well. His eyes then go dewy as he reels off all the American football that a fan could watch on television with a wife more sympathetic to it.

Nevertheless, he is certain that he will be spending some of his time post-retirement in America watching it. 'I've never seen a regular-season game in the NFL, because by the time I had the money to do it I didn't have the time. I'll definitely go over for a week. If you timed it nicely, you could get in six games, although it would obviously be at the expense of talking to anyone in your family. You've got Saturday afternoon college football; Sunday night there's pro football; Monday night_.'

He goes on like that for a while, and there are many other astonishing displays of American football expertise throughout our conversation. When we part he says with more concern than is seemly in a world champion: 'Don't make me out to be a geek.'

Well, he wasn't wearing an anorak and he is one of the greatest sportsmen Britain has known, but that's about the best that can be done.