Leinster head coach Leo Cullen says it's important his side impose their own game on Toulouse in tomorrow's Heineken Champions Cup semi-final.

The last four meeting sees the competition's two most successful sides pair off, defending champions Toulouse five-time winners of this competition, while Leinster have four European stars on their jersey.

And while Toulouse come into the game as the holders, it's Leinster who will be favourites to get back to the final, having averaged 50 points and seven tries per game across their six matches to date.

The province will also have home advantage, with 37,000 tickets sold for the Aviva as of this afternoon.

Leinster have also been able to name an unchanged team from last week's quarter-final victory at Leicester, with the only change to the matchday 23 seeing Ciarán Frawley replace the injured Tommy O'Brien among the replacements.

Ugo Mola's Toulouse reached the last four after eking out slender wins against Ulster (over two legs) and Munster in previous rounds, and Cullen says his side can't afford to play to the French strengths.

"That's always crucial, what will the opposition try to do to us?" he said.

"We turned up at Welford Road [v Leicester Tigers], we had a fair idea what was coming and our guys dealt with it pretty well, particularly in the first half. The second half, not so well.

"We need to see how Toulouse approach the game, we saw how they played against Munster, they played a strong territory game early.

"Munster were firing into everything as you'd expect, and that's what we want our guys to do as well. For us to be able to impose our game plan on Toulouse is what we really focused on this week, and that's both sides of the ball, attack and defence.

"What Toulouse give us, with the pictures they show us, and again how they attack and defend, I'll be curious to see. They have traditionally in some of these play-off games played quite tight, not given too much away, and waited for the game to break up later.

"You've got to be able to adapt on the day, and see what are the opposition throwing at us, and also the conditions and the referee, and all those external factors."

The Leinster coach (above) says he's unsure whether fatigue will be a factor, despite the grueling nature of Toulouse's win against Munster a week ago, where they had to play 100 minutes of rugby, while also not being able to manage their minutes due to a busy Top 14 schedule.

"Does it take a bit of a toll? They're used to the grind of Top 14 anyway, week on week, so it's the size of the game," he said.

"We'll wait and see, it's not something we will rely on ourselves; their fatigue.

"For us, we just want to impose our game regardless of what the opposition has done the week before. We tried to get that balance between having some intensity this week, recovering from coming back late on Saturday night, and just managing the group well this week.

"We've got to be able to impose our game, when we have the ball and when we don't have the ball. When you're at the Aviva, there's a certain familiarity, but we can't rely on it. We have the crowd's support, it feeds into the energy of the team," he added.

The Leinster squad held their captain's run at the Aviva Stadium this morning, with no injury scares to report after their final session.

And Cullen says he believes his players are ready for the biggest game of their season.

"It's a fascinating challenge, we have huge respect for them as a team. We're just excited to get going at this point, dying for kickoff.

"Let's get it on now, it's what we're excited about, and just rip into the challenge of playing the top team of Europe over the last 25 years of the competition.

"It doesn't get much better really, we're excited to get going."

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