The sight of Delon Armitage having to prop up his shoulder with a sling at the Heineken Cup launch in Paris last Monday would have been something of a relief for Leinster.

Not that the defending European champions have reason to fear anyone, but rather because the England international has made a habit of getting into scrapes with their players of late.

It took him only two minutes to start a scuffle with Niall Morris during a pre-season friendly at Donnybrook in August, and Irish fans – not to mention Brian O'Driscoll – will be well aware of Armitage's on-the-edge style following last year's Six Nations encounter at Croke Park. The dynamic full-back scored a penalty and a late try in Ireland's 14-13 win over England but his performance will also be remembered for a cynical hit on the Irish captain in the second half.

Armitage will miss next Friday's Heineken Cup opener at the RDS after he dislocated his shoulder in London Irish's thumping English Premiership victory over Gloucester three weeks ago. But despite the Exiles' impressive start to the domestic season, he suggests they are heading into the unknown from next week on.

"I think we're looking forward to it and we're very anxious because we don't know what to expect. Obviously after being in the Challenge Cup last year and coming up into the Heineken Cup, you're playing against the best in Europe. There are no easy games."

As well as his undoubted flair, Armitage has put the less glamorous side of his game down to cutting his teeth in French rugby. Born in Trinidad, the 25-year-old spent much of his teenage years in the south of France, where he played with Racing Rugby Club de Nice. He made a sole appearance for France's under-16 team – after which he was judged too small to make it – before his family moved back to England and he joined the London Irish Academy.

Since then, he's emerged as one of the few plus points in a difficult couple of years for England, and, along with his younger brother Steffon, he's become an integral member of the London Irish squad that travel to Dublin this week.

"We know obviously starting against the champions it's going to be a tough game and I think that's going to set the tone for the tournament," he says. "Especially playing in Dublin on their home ground – I mean that's as tough as it gets.

"We need to be up for it or otherwise we're going to be at the back of a big score. We're looking forward to it and we're not here to make up the numbers anymore. I think at London Irish, we've grown quite strong as a team and as players. There's a young squad and we're looking to do well in this tournament."

Michael Cheika's side will know what to expect, having lost 24-8 to the Exiles in August. That was Leinster's first home game since defeating Leicester in last season's Heineken Cup final and Armitage is hoping London Irish can spoil the party once again. But he was impressed by the 6,500 capacity crowd, and with Leinster missing a number of high-profile players that night, Armitage knows his side will face a much sterner examination at the RDS.

"We had them in pre-season and it was very tough over there with the Irish crowd. It was a brilliant atmosphere and I think it's going to be even better when we go out there to play. I'm very disappointed that I'm not going to be involved. I'd like to even fly out there with the boys just to soak up a bit of that atmosphere.

"But I don't think it comes any tougher than a great team like Leinster who've been playing really well in the Heineken Cup. I think they deserved it last year for the way they played through the tournament. Their internationals, the likes of Brian O'Driscoll, lead the team really well. I think we need to be awake at the kick-off – if we're still on that plane we're going to be in trouble."

A team that lost by a point to Leicester in last year's English Premiership final is unlikely to be fazed by a trip to the RDS however, and Armitage insists London Irish will play their natural game in the hope of coming away with a win.