Leinster boss Leo Cullen admits his side place "huge pressure" on themselves as they begin a campaign for a fifth star.

Last winners of the Heineken Champions Cup in Bilbao in 2018 when they edged past Racing 92 in the final, there have been slim pickings on the European front since.

By the time the final of this season's competition rolls around in May in Marseille, almost four seasons will have elapsed since that last trophy-lift in the Basque Country.

Talk them up as the Leinster camp have in the last fortnight, Bath today, with six Champions Cup debutants, are not expected to provide much resistance in their Pool A round one clash.

But the Blues boss is wary that there’s always the chance of a "sucker-punch" and that not getting caught cold, like how they went down to Saracens in the 2020 quarter-final, is vital to their ultimate goal.

Cutting corners today is simply not an option.

"There’s huge pressure that we put on ourselves, because that’s what we’re after and it’s an incredibly hard thing to do because there are so many good teams around Europe," he said ahead of the 3.15pm kick-off against the Premiership's bottom team, who have yet to win a game this season.

"We came unstuck last season away to La Rochelle [in the semi-final].

"I’m just thinking of the timeline, because you mentioned Bilbao.

"It was a very unusual scenario where you play Saracens in an empty stadium the week after we played Ulster in the [Pro14] final.

"Again, just that feeling when you get that sucker-punch and you don’t have the answers to be able to deal with it.

"So for us it’s just about making sure that we’re open when we find ourselves in that situation because we will find ourselves in that situation again.

"So it’s important that we all learn.

"That’s not just young players, it’s everybody, staff included, backroom team, coaches, that we understand when it comes to the top end of this competition it’s as close as you’re going to get to top end international rugby."

Almost five years ago Cullen handed full European debuts to six young guns when the sides met in the Aviva for a pool stage tie.

Among the rising stars that day was Garry Ringrose and he'll line out alongside Ciarán Frawley in the centre today.

Earlier this week 26-year-old Ringrose committed to the province and Ireland until the end of the 2024-25 season and former lock Cullen was pleased with that bit of business.

"Garry is someone who is so curious, inquisitive and he works so hard on all aspects of his game," he said of the Dubliner, who has scored 10 tries in 37 Ireland appearances.

"It's not just out on the training pitch, it's the technical, tactical, physically, he works all aspects of his game all the time.

"He has a great mindset, always looking to improve, growing his leadership as well.

"I know he's a very important player with Ireland and he's certainly a very important player with us. It's great news for Leinster and Irish rugby that he's committed for another three years.

"You saw during the November series how pivotal he has become. Even talking to some people connected in around the All Blacks, he's definitely a player they would look at on both sides of the ball."

"He's impressive not just from an attacking point of view, but from a defensive point of view as well, some of the reads he makes, he's a very very smart player and I think most teams would recognise that. He has that ability.

"I always think 13 is such a difficult position to play, particularly from a defensive point of view, so for us to have someone with that level of intellect and interest in the game is hugely valuable."

Inside Ringrose is 24-year-old Frawley, who was part of Andy Farrell’s November squad but didn’t get any game time when Ireland saw off Japan, New Zealand and Argentina.

"He’s a great natural footballer, Frawls and to have that second distributor - someone who’s comfortable running the team as a '10’ - at ‘12’," enthused Cullen of the Sydney-born back, who will make his sixth European appearance.

"A second-ball player is something we’ve talked about a fair bit in the past and the advantage it gives the team, and Ciarán is still young.

"He’s played plenty of games for us at '12’ and a bit at ‘10’ as well, even a bit at ‘15’.

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"That is just an indication that he’s a rounded footballer, and he’s got that ability to run and carry, and his kicking game is very good as well. Yeah, I’m looking forward to seeing Frawls play, it’s a great opportunity for him.

"He was away with the November squad, didn’t get to feature, but by the sounds of things he’s not a million miles away from that. Yeah, he’s been a very, very important player for us."

"Obviously he was unlucky during the course of last year.

"He was managing a shoulder injury that he eventually had surgery on towards the end of the season.

"So he had a bit of disrupted tail end to last season but he worked hard over the course of pre-season and has got himself in good shape now, and another great window for him this week."

Despite being hit with a Covid outbreak that sees three unnamed players unavailable, Leinster are 31-point favourites to see off Stuart Hooper’s side.

The drive for five starts here.

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