For a decade they have been the most powerful force in European rugby and as this season’s Champions Cup gets underway in Dublin tonight Leinster have picked a team that looks designed to assert its authority on Pool 1 from the outset.

Fellow former champions Wasps provide the opposition to the defending champions, but second of their triumphs was achieved by a very different squad a long time ago.

Leinster’s four successes have all come in the interim and led by Johnny Sexton, who also was also the on-field mastermind behind Ireland’s Grand Slam triumph last season, they open with six members of the back-line and half a dozen of the pack, include the same front five, that beat a powerful Racing 92 side in that Champions Cup final in Bilbao.

Having gradually reintroduced their big guns Leinster have meanwhile managed to maintain winning form in the Pro14, leading their Conference with a record matched only by Glasgow, across the competition as a whole, in winning five of their first six matches and as reigning champions they go into Europe as principal standard bearers in what could prove a telling season in the longer term.

While the Celtic nations were effectively bullied into the overhaul of the Champions Cup by the superior commercial clout of English and French clubs, last season suggested that they have found a way of redressing the competitive balance. Previously that had been achieved by the device of allowing the Celtic League, which became the Pro12, to operate as much as a development arena as a competition in itself with the lack of relegation supplemented by a system of qualification for Europe which ensured that all of its competing countries would have guaranteed representation levels in the Heineken Cup.

English and French insistence that straight competition was required effectively prevented them from continuing to protect leading players from over-exposure, reducing their effectiveness in the big Champions Cup and international matches. However last season’s introduction of South African teams and the consequent innovative re-structuring into a two Conference system with three teams from each qualifying for extended play-offs and an additional play-off match for the seventh qualifier, has once again allowed coaches to manage their resources to what is perhaps even greater effect.

That was reflected by the way that Leinster were able to sustain challenges in becoming the first Celtic team to win the domestic competition and the Champions Cup in the same season, even as Ireland were winning that Grand Slam, while Cardiff Blues contributed to another first for the Pro14 in making it a European double by winning the Challenge Cup. This season will tell us a great deal about whether it was pure coincidence that all of that happened immediately after the re-structure and the Celtic contenders including, for the first time in five years, two Scottish representatives, look set to be competitive in every one of the five pools.