Leinster players celebrate after the win over Racing 92. Three years after my career has ended at least I know the changing room will stay lodged in my mind until I’m old and grey. Photograph: Ramsey Cardy/Sportsfile via Getty Images

Champions Cup winners Leinster were paraded in front of their supporters at a special homecoming event in Donnybrook. The Irish side defeated Racing 92 of France by three points in Bilbao. Video: Bryan O'Brien

When Remi Tales’ drop goal frisbeed into the crowd I was taken back to the best feeling in the world . . .

Going up to get the trophy is always special and the lap of honour is a lovely walk, looking fans and family in the eye, but it’s what follows that I will cherish forever.

Behind the changing room door is the only time the group are shielded from everyone. Just you and your team-mates. This is the moment that stays with you and, of course, it gets taken away so quickly. There is a plane to catch. People get scattered on the night out. The homecoming is hectic with Munster looming in a week’s time to spoil the party.

So that little window is what stays with me.

James Ryan, Dan Leavy, Jordan Larmour – all the young lads – must feel like this is how it’s always going to be. Play, win, celebrate, train, win some more. Unless Leinster and Ireland morph into the Kilkenny hurlers or the All Blacks – and that is possible – these days are precious and few. Six years of anguish can flash past. The best player in the club could leave without warning. Injury will almost certainly snatch a season in your prime.

The coolest moments are few and fleeting but three years after my career has ended at least I know the changing room will stay lodged in my mind until I’m old and grey.

We had Heinekens and each other. No better craic will ever be had. We were vulnerable, shattered, happy Sitting in Twickenham after toppling the world champions on their home patch was the first momentous win of my career. 2009 in Murrayfield was so special but we were on the bus to the airport very quickly. But 2011, after beating Northampton at the Millennium, we got the rare gift of added time. We were delayed for three hours after some poor sod – can’t remember who – was too dehydrated to relieve himself for the drug testers, so we couldn’t leave. We had Heinekens and each other. No better craic will ever be had. We were vulnerable, shattered, happy.

Pure relief Thinking that this private party was happening down below put a massive smile on my face leaving the stadium. I knew Larmour or one of the young lads was experiencing that elation for only the second time (Paddy’s Day being the first). For others, like Rob and Johnny, the emotion would be pure relief after waiting for so long to reach the summit.

Christ, have the fans been going through this all the way back to 2009? I could barely watch the last 10 minutes. The hurt if we lost would have been terrible. It was too much!

Only afterwards did I relax. Being inside the San Mamés stadium, for the first time I think I grasped what it’s about to follow Leinster. I mean, to really follow a team that represent where you come from.

The stress was torture. As a player it’s the complete opposite. We struggle in the build-up but the field offers a release, mainly because we can somewhat control our destiny. Robbie Henshaw and Garry Ringrose were swamped in midfield all game but they believed their outhalf would give them an opportunity and eventually each of them made important inroads.

Johnny Sexton’s mindset and belief was infectious, he continually drove Leinster and the others responded. Photograph: David Rogers/Getty Images It was such an even contest as most of Leinster’s strengths were met with equal force while Teddy Iribaren had the game of his life. This allowed Racing to control the tempo for over 70 minutes. About 20 minutes longer than would have been the case on a dry day.

Thankfully, the one thing they could not influence was Johnny Sexton (Bernard Le Roux did try). It wasn’t his play-making or talk with Wayne Barnes or game management but his absolute resolve to keep Leinster on their desired course (we are what we do every day and a Champions Cup final is any other day).

His decision to go to the corner and take quick taps rather than kick the points was Johnny’s refusal to play conservatively. He pushed passes firmly believing that Racing would buckle under the strain. His mindset and belief was infectious, he continually drove Leinster and the others responded. The missed penalties, both from 49 metres, and being constantly behind on the scoreboard never eroded his confidence.

Eventually Johnny performed a simple catch and pass that forced Henshaw through a gap. On they went into Racing territory to level matters and after Teddy Thomas had his meltdown Leinster eventually took the lead.

(Similar credit goes to Donnacha Ryan after smashing his collarbone in an early lineout. It reminded me of Trev Brennan’s influence on Toulouse. The Racing players were drawn to him. For Jacky Lorenzetti, Ryan and a few others will be the smartest money he ever spends if they keep playing for each other like Saturday.)

Breath energy The final will be analysed in finer detail further down the line. It has little value this week. Switching over to Munster in the RDS on Saturday will force changes in the starting XV. Robbie Henshaw and possibly Luke McGrath, Sexton and Isa Nacewa will be forced out while others will be picked to breath energy into the group. Players like Jack McGrath must take over the leadership.

The cultural dynamic in Leinster means there is an expectation on the hybrid side that faces Munster to deliver Managing resources has become the great skill of Leo Cullen: Andrew Porter could start so Tadhg Furlong barrels into the semi-final for the last 20 minutes or James Lowe can give them a lift but that means dropping Scott Fardy if Jamison Gibson-Park needs to play. Either way Jack Conan has earned a start.

After two poor performances post Grand Slam in Swansea and at home to Treviso, the onus is on certain players to prove they are not second string. That’s good peer pressure. The cultural dynamic in Leinster means there is an expectation on the hybrid side that faces Munster to deliver. For many it’s an opportunity to alter Leo’s future selections. By helping to shape Leinster’s greatest ever season they can approach him with a valuable bargaining chip.

Change occurs every summer but Isa moving on is substantial. I suspect it will be viewed internally the same as usual; you can’t hold onto players forever. Leinster lived on after Leo Cullen because Dev Toner stepped up. We survived after Rocky Elsom’s one season because Seánie O’Brien was bursting at the seams to play. The club will always move forward, it’s about the footprint he leaves behind. When Leinster win under the younger leaders the Isa lessons will be evident.

That needs to start this weekend.

Clean up any mess Bath have recruited a great rugby brain and man of high integrity. Girvan Dempsey was the responsible figure I never was. For 12 years I played in a Leinster team with Girv underpinning everything from fullback. Myself and Denis Hickie had licence to do whatever we wanted safe in the knowledge that he would clean up any mess.

Bath have done well; Girvan Dempsey was the responsible figure I never was. Photograph: Oisín Keniry/Inpho And I caused plenty when trying the spectacular, or popping up at first receiver or streaking off my wing just for a run, all the while knowing Girv would mind the house. When shifting to centre with Shane Horgan on the wing we could keep inter-linking in attack because of the confidence he imbued in us.

Girvan understands the game. He always knew to show the kicker plenty of grass before timing his run into the space. It looks easy when it’s happening but get that wrong and the opposition can kill you. Look at Rob Kearney on Saturday or any game this season and see a great fullback who learned from the positional master.