Back then, it all seemed so easy to Dave Denton.

There he was, in the infancy of his professional career, lining up in a Heineken Cup semi-final. To get there, Edinburgh had taken the scalps of some giants of the game, having beaten London Irish, Cardiff, Racing Metro and, sensationally, Toulouse. Frankly, this European rugby business all seemed a bit of a lark.

That, though, was then: season 2011/12. What followed for Denton was the most brutal reality check possible, as his own form slumped and Edinburgh reverted to type. In the following Heineken Cup campaign, it was their sheer awfulness which caught they eye as they became the first side in tournament history to go through their opening two games without registering a single point.

Small wonder that Denton now appreciates how precious these big European occasions can be. When he and his Edinburgh team-mates line up against Perpignan at Murrayfield late this afternoon, there is little danger of any of them taking things too lightly. Win and they will keep their European dream going for at least another week; lose and it will be over for another year.

"The young guys coming into the Edinburgh team two seasons ago were really naive about the Heineken Cup," recalled the No.8. "We thought it was quite easy as the first time we played in it we got to the semi-final. It sort of felt like business as usual but we got a very rude awakening the season after that when we did not win a game.

"So it is a tough competition. If you lose one game you are just about out of it. Lose two games and you are pretty much out, but we have a fighting chance to still get through to the knock-out stages. It is really exciting and puts a lot more interest on the game."

Already, Edinburgh's Heineken Cup efforts this season have produced many more echoes of that 2011/12 campaign than last season's disastrous sequence of performances dished up. They opened with a shock win against Munster, then grabbed a second unexpected win over Gloucester at Kingsholm last month.

Along the way, though, they have also been guilty of making costly errors, as they did against Perpignan in France last October when Edinburgh quite literally kicked away their 7-3 half-time lead. Perpignan capitalised on some loose clearances - albeit with some dazzling counter-attacking play - to post a 31-14 win.

Yet that was Perpignan's only success this season and their interest in the Heineken Cup is almost certainly over. Despite that, they have picked something close to a full-strength side, countering suggestions that they would send a team of second-stringers over for the game.

James Hook, the veteran Wales fly-half, has been moved to full-back, allowing former Scotland under-20 internationalist Tommy Allan, who controversially opted for Italy at senior level, to fill the playmaker's berth.

Allan made an appearance as a replacement in the earlier game against Edinburgh, when Denton was an interested, if hugely frustrated, spectator. "That was the game where I had to pull out at the last minute," Denton recalled. "I was there watching, but it was a long way to go to watch a game. The most frustrating thing for us was that the margin of victory for Perpignan was much bigger than it should have been. We went into half-time in the lead and were physically on top of them which was a big feat considering they have two 140 kilo locks and a big pack.

"We did well to get into that position but then we switched off and they scored two quick tries. You cannot afford to do that in top-flight rugby. When you make one mistake the good teams will pounce on you."

When Denton looks back to Edinburgh's giddy run to the last four almost two years ago, his fondest recollections, perhaps not surprisingly, are of that magical Saturday afternoon when close to 40,000 fans - a British record for a quarter-final - turned up at Murrayfield to watch them beat four-times winners Toulouse.

"It was something special," he said. "The people of Edinburgh got really behind us that day and I would love to put them in a position to do that again. The people who turned up for that Toulouse game showed the fan base we have in the city.

"We need to tap into that. Beating French teams at home is a very good place to start and we are more than capable of doing that. We have shown in the last month or two that we are a real, physical side and that is how we are going to win matches."

After their extended period of rest due to the postponement of the New Year's Day derby with Glasgow, a fired-up Denton is undoubtedly good news for Edinburgh ahead of a crucial game. So, too, is a fit-again Matt Scott, the Scotland centre named on the bench after two months out with a hand injury.