Leicester Tigers head coach Matt O'Connor believes that Leinster Rugby will have to "show defensive energy" if they are to defeat Racing 92 in the European Rugby Champions Cup final in Bilbao on Saturday.
"We know we can get better and we feel that we need to get better tomorrow in a lot of areas", he said.
Cullen sought the help of former England coach Stuart Lancaster and the team haven't looked back since, with Lancaster bringing his experience and tactical know-how to the squad.
Whereas Racing, beaten finalists in 2016, are hoping to upset the odds and pull off a victory against a Leinster side packed with Irish Grand Slam winners. His absence will undoubtedly make their task harder although they still have a squad full of internationals including World Cup victor Dan Carter in his final season at the club. "The atmosphere was electric and when we ran out to see all the colour, the flags waving, and the noise was off the charts so it was a very special". "At our level it is all about details and our discipline was poor in the first half", flanker Yannick Nyanga said.
Racing came close to forcing extra time after the buzzer when stand-in flyhalf Remi Tales's drop goal flew just wide.
A pre-match hamstring injury spoiled Carter's European swansong, and Lambie's final lasted less than three minutes, the South African damaging his knee on an early break.
Leinster coach Cullen and Racing counterpart Travers are not just fighting it out to lead their sides to glory.
The normally free-flowing Irish side, who had scored 31 tries in eight games in the competition, were being kept at bay.
The 6-6 scoreline became 9-9 and then 12-12 as Iribaren landed four of his five penalty attempts and Sexton finished with three.
Sexton suffered his second miss from long range, following a James Ryan lineout steal, and as the contest became increasingly scrappy, Iribaren's only penalty miss let Dan Leavy off the hook for a high tackle.