Edinburgh's Allan Jacobsen is determined to end his career on a Heineken high

So who starts calling the shots? Who provides the voice of exhortation? The emergence of tyro players such as Stuart McInally, Lee Jones and Matt Jones has been one of the most compelling themes of Edinburgh's season, a new generation with big ambitions, and all three must have been desperate for the fourth try. But so was Allan Jacobsen, a man whose teenage years are a distant memory, but whose desire still burns as brightly as ever.

So as the Edinburgh forwards trotted up to the set-piece, there was Jacobsen already, squat and ageless, the first man in position. It told you everything you needed to know about how much this result meant to Edinburgh. It would also have told you that they were going to get that fourth try. From the way Jacobsen barked instructions at his pack it would have been a travesty if anything else had happened.

"These times in games make the difference between winning and losing," said Jacobsen afterwards. "The scrum was perfect and that let Netani Talei do his job at No.8. When we do these things right we can score against any team at any level. And we did."

It would underplay Jacobsen's all-round – and yes, the term has a literal dimension – qualities to call him a stalwart of this Edinburgh side. He made his Heineken Cup debut for the team, then known as Edinburgh Reivers, in 1999 when he came on as a replacement against Grenoble at Netherdale. Yesterday's match was his 68th in the Heineken Cup for the capital side, a club record.

At 33, he should really be throttling back on a career that has also brought him 60 caps. Yet in those seconds near the end – and, in truth, on umpteen other occasions when he scuttled off with the ball and drove low and hard at the London Irish defence – his foot was clearly still on the gas. Somebody might someday call time on the Jacobsen career, but they'll have to drag him out backwards when they do.

And Edinburgh's Heineken Cup run has only served to energise the man from East Lothian who served his apprenticeship as a plumber before committing himself to full-time rugby. There is something wonderfully old school about him, but nothing obviously old about the way he plays this game. Sure, he knows he's living on borrowed time, but he's going to extract every ounce of value from the loan.

"Over the past four years, since the 2007 World Cup, I've had it in the back of my mind that I don't know how long I will be playing for," he said. "I've seen a lot of boys go because of injury and suchlike, and you never know if that might happen to you. I've been lucky. I think I enjoy it more now than when I was younger. When you're younger you think you're going to play forever, but when you know it's going to finish at some stage you just try to get as much out of it as you can. I just appreciate it a lot more."

Jacobsen was there in 2004, already a senior player, when Edinburgh made their first and only previous appearance in the Heineken quarter-finals. Back then, he thought the club had cracked it as a European force, so the eight years since have been a period of uninterrupted dismay. Yet when the club seized a late win at London Irish's Madejski Stadium in the first game of this season's campaign, he sensed something might be afoot. Since then, they and he have gathered momentum with every passing game.

The Edinburgh crowd love the man they call Chunk. They have a limited range of chants at Murrayfield, but those they do have all seem to sing his praises.

"We have Chunk, he's our man," goes one, to the tune of This Old Man. "He's the prop from Prestonpans." Can you imagine it in the throats of 30,000 Edinburgh fans descending on Twickenham for the Heineken final in May? Probably not, but Jacobsen and his mates have confounded the odds in every European game they have played this season – and if there's any justice in the world then the fairy-tale story is not about to end just yet.