Ospreys captain Alun Wyn Jones feels they do not understand their own potential, but hopes they "can turn a few heads" in Europe this season.
They face Racing Metro, Northampton and Treviso in the revamped European Cup's Pool Five.
Ospreys, unbeaten in the Pro12, face Cardiff Blues before hosting Treviso in their Euro opener on 19 October.
"We don't realise the potential we've got, and if we fulfil that we can turn a few heads." said Jones.
The Wales and British and Irish Lions star has experienced more lows than highs in Europe's past incarnation, in the Heineken Cup, including a 29-28 quarter-final defeat by Biarritz in 2010.
And while Ospreys hope to remain unbeaten going into the Treviso clash, Jones admits they have "a bit of work to do" on performances so far.
|Ospreys captain Alun Wyn Jones|
|"We can't definitely come and say "yep, we're going to do it, we'll get to the quarter-final. We're not that team at the minute."|
There have been a lot of changes at the Welsh region since the summer departures of Lions Adam Jones, Ian Evans, Ryan Jones and Richard Hibbard.
They have already beaten Treviso 44-13 this season in the Pro12, but Jones does not think that will have a bearing on their clash against the Italians.
"A couple of the scorelines have been a little bit flattering," said Jones. "And we've been our own worst enemy with the penalty counts and left a few points on the park in a couple of games.
"So there's still a bit of work to do, but we're ramping up ready for the European games."
Jones, 29, believes they have an opportunity to make a mark in Europe, but cannot be expected to reach the knock-out stages.
"There's an opportunity there," he added. "We've faced Northampton in the past, but having Racing Metro in there and Treviso, it's going to be tough.
"We can't definitely say 'yep, we're going to do it, we'll get to the quarter-final'. We're not that team at the minute; we haven't got that culture.
"We want to work hard to earn the right to get out of that pool."