On days when Imanol Harinordoquy is getting on the end of sweeping wide moves to score in the corner, the first thing that springs to mind is Ireland's annihilation by France in the 2003 World Cup. And when he starts palming down line- out ball without the good grace to use two hands, you think of any number of days in Paris when the away team were only making up the numbers. What you do not contemplate is that Harinordoquy leaves the scene early, knowing his team are beaten. And that his opposite number has already secured the man-of-the-match award.

Last week the rest of Europe woke up to the prospect of Jamie Heaslip as a top-quality international No8. He scored a thrilling try that will still be on-screen when the awards are being handed out at the end of the Six Nations; he opened the door to another six points through forcing penalties in sight of the sticks; and he carried ball off the back of the scrum as if it were an unopposed training spin.

Not only was this a unique package but its delivery was beautifully timed, for the 25-year-old was in need of something special. That is what happens when you plateau after reaching an impressive peak.

In Ireland we forget that Heaslip has only 14 caps. For all of 2007 he was hopping impatiently from one foot to the other while the then coach Eddie O'Sullivan looked him up and down. He had been doing a first-class job for Leinster, with eight tries in the season leading to the World Cup, but O'Sullivan was sceptical. Every time Heaslip touched down the Ireland coach would shake his head at a routine that sometimes involved the ball in one hand and a celebratory wave with the other. When he called the young No8 into Ireland squad sessions he would go out of his way to leave a layer of frost between them.

"At least I scored," Heaslip says. "I was aware of that [coolness] at the time but I'm not going to change my personality. I'm sorry if I score tries. That's all I'm really going to say about that. If he didn't pick me for personal reasons then that was his prerogative. If he didn't like me celebrating when I scored a try that's fair enough but I'm still going to do it. That's what you're out on a rugby pitch to do, to score, and I'm over the moon when I score. If that was one of his reasons fair enough but at the end of the day I think the rugby speaks for itself."

Neither does Heaslip think that being left out of O'Sullivan's World Cup squad turned out to be a cloud with more silver than grey, given the grief that attended that exercise. He figured his performance against Scotland in the last build-up game had warmed a seat for him on the plane. When he woke up the next morning the boarding pass had gone elsewhere.

"That World Cup squad was something I aimed to do, something I wanted to get into and it was a goal of mine during the season that led in to it. I'd been involved in all the camps and I'd been involved in the game on the Saturday and he announced the squad on the Sunday. And I was gutted that I wasn't put in and I'd never say that it was a blessing in disguise."

O'Sullivan eventually gave him the gig after the dismal start to last season's Championship, moving Denis Leamy to No6, and immediately Heaslip brought to international level what he had been producing for Leinster: an all-court game. It did not earn him widespread acclaim because Ireland were so ordinary at the time, but his name was one of the first on the team-sheet.

Then Rocky Elsom came to Leinster and some of the gloss went off Heaslip's contribution as a carrier, which had been a core feature of his game. And so we reckoned he needed a lift when the Six Nations took off, something to take him clear of Leamy, whose fitness is good enough now to get him back in the squad.

"I don't know about form-wise," Heaslip says, unimpressed that the issue is being raised. "I don't think I've gotten on the ball that much. Or as much with Leinster. I think it's just the way we were playing I wasn't getting on the ball that much. But I was still happy enough with the things I was doing. It was a bit frustrating but you can't start bitching or moaning about it really. You've got to just get on with your tackles and turnovers. I was happy enough with everything else bar not getting on the ball. I'm not going to get too stressed about it."

His name will feature larger now in Lions talk where so far this season the form of Wales's Andy Powell has been the dominant feature. "He's a good player that guy – he's really strong," says Heaslip. "If you wanted to believe that already he has his seat on the plane, well the plane ain't leaving for a while. It's what happened with me with the World Cup squad. Nothing is written in stone until you're on that plane and you're going. You can't get carried away. Just play and let it speak for itself."

Imanol Harinordoquy would say he is making an articulate case.

Brendan Fanning is rugby correspondent of the Sunday Independent