The four-time champions travel to their United Rugby Championship rivals having won three of their Pool A games by comfortable margins to reach the knockout stage, but Cullen warned that the next fortnight will be a much harder task.

“We’ve got some great challenges ahead now – at Connacht next week and Connacht back at the Aviva – two huge games for us in Europe,” he said.

“It’s just making sure we prepare well. We’ve got a short turnaround and the week after. They are two huge weeks for the club. Hopefully we’ll get plenty of support on the road and then back at the Aviva. Down at the Sportsground it’s going to be a tough old challenge.

“It's great to be in the play-offs for Europe. Now it’s trying to just get through to the next round. Obviously, this time it’s slightly unusual in the fact that it’s a two-legged last 16 which we haven’t had before.”

Leinster hooker James Tracy is also wary of the threat Connacht will pose during Friday’s contest.

"We’re under no illusion that we’re going into the lion’s den,” he said. “Going down to Connacht is going to be a tough battle. But we’re going to have a great week’s prep and go firing into it.”

Meanwhile, senior coach Stuart Lancaster has revealed that vastly experienced fly-half Johnny Sexton, who played a key role in all four of Leinster’s European Cup triumphs, is raring to go after being sidelined since January.

“He’s still pretty competitive,” Lancaster said. “He’s keen to come back in. It’s not like his enthusiasm has diminished in any way, shape or form. He’s desperate to get up to speed so he can lead from the front because he’s the captain of the team.”

Leinster Rugby head coach Leo Cullen says his side are relishing their two-legged Heineken Champions Cup Round of 16 encounter with Connacht Rugby, which starts with a tough examination at The Sportsground on Friday.