If anybody is entitled to have a split personality on this tour then it is Eddie O'Sullivan. A forwards' specialist in his time as USA Eagles' assistant coach, now a backs' specialist as Irish assistant coach, O'Sullivan was with the travelling Eagles in Ireland during the World Cup and is now with Ireland in America.

But he smiles and says he has a simple rationale for resolving any sense of confused identity. "Well, there's one thing that counts, and that is who writes your pay cheque. It's called professionalism. When you're an amateur you can start talking about your head and your heart but when somebody cuts you a pay cheque at the end of the month there's no doubt in your mind where your bread is buttered."

The former Garryowen and Munster man was assistant national technical director for a year and a half, and then technical director for a year as well as assistant coach to the national team until reverting to the Irish cause.

Based first in Colorado Springs and then primarily out of San Francisco, and moving around for clinics and national squad sessions he says "there was a great travel dimension to it", but few appreciate the logistical difficulties facing US rugby more than O'Sullivan. "The game is still amateur and it's such a big country. You've four time zones, three climates and a continent, and it's still a minority sport."

And there's their problem with money. They don't really have any. "The costs of running the game given the geography of the situation is quite expensive. Sponsorship is hard to come by because they don't have any product yet."

O'Sullivan agrees admittance to the Olympics would be a huge catalyst. "The other thing is that it would attract top athletes from other sports into rugby. To be an Olympian would be a big deal in America. With a population of 150 million you'd get more people over 6' 10" and you'd get more people of 6' 4" who can run the 100 metres in 11 seconds. But their sporting structure here is inherently professional, so most people either play pro ball or no ball. Rugby going professional would be good for them. "

Hence a proposed inter-city league backed by Sky Sports - which he thinks might begin in two years.

Because of the difficulties facing US rugby O'Sullivan says "there is an enthusiasm for rugby which defies logic. I've told people in Ireland that if Irish rugby had the problems that American rugby has, we wouldn't play rugby."

He cites someone who drove from San Francisco to a clinic in Dallas. "That's like getting in your car in Connemara and driving to Moscow. It took him three days to drive. He paid his own clinic fee and expenses. That would be extreme but people would think nothing of driving six to eight hours for a clinic and paying their own expenses, and they run teams out of their own pocket."

As Eagles' forwards coach dovetailing as coach of the Buccaneers' juggernaut, to orchestrating the new breed of young Irish backs, O'Sullivan says he would be "torn between the two" in terms of personal preference. "It helped me as a coach overall."

A bright, lucid and articulate talker about the game, O'Sullivan believes there's a really good crop of young talented Irish backs coming through. "We just have to make sure we keep playing to our strengths, which at the moment is in our backs."

For him Argentina was an acid test without three first-choice backs "and the good thing was that we didn't go into our shell. We tried to play our game. We didn't win the game, but that was for other reasons."

On Saturday's match he said: "The danger for us is that if we don't create a good platform to play a structured game we could have problems imposing our pace on the game. Then you get into one of those games where if you don't shrug a team off you just spend the day trying to put them away. And in any game of rugby, no matter how weak you are, if you go into the last 10 minutes and be one score behind you can win the game. So the challenge for us is to be very structured and impose ourselves on the game. If we don't, they'll cause us problems."