Luke McGrath has revealed that he was told on Thursday after training that he would be starting the URC final in place of the injured Jamison Gibson-Park.
The final teams were announced a day earlier than usual to help promote the Croke Park decider, so on Thursday rather than Friday.
It was after that official announcement that McGrath knew he was back in the No.9 jersey - and despite feeling nervous about starting on the big occasion, he played a stormer.
"It's amazing," said the 32-year-old. "It's more relief than anything that we got it done. The lads are so happy and the staff are so happy.
"I kind of knew during the week that there was a good possibility, just with Jamo's hamstring or whatever, so he gave me the nod that there was a bit of a possibility that I could do it.
"But I got told on Thursday, basically after training, that I would be starting. So nervous enough, obviously, but unbelievably excited and obviously it was an unbelievable day out there and one that I'll never forget.
"I thought we were really good as a team in the first half, we built that score and that allowed us to build into the second half a bit.
"I thought we were really clinical. The lads up front were brilliant in the scrum, the scrum penalties just kept the momentum going and it was a long time coming, so it's all that bit sweeter now."
McGrath described winning the trophy at Croke Park as "unbelievably special", adding: "Obviously we've played here three or four times now but every time we come here it's just a bit more (special), the players even feel it coming out, there's proper history here and it's incredible to play in front of a crowd like that today.
"And just doing the walk with that trophy, I've been to a few Dublin matches here over the years growing up and to do that walk with the trophy is pretty special, it's one that we'll never forget.
"We've lost finals in the last few years and it was really tricky, but all week we just spoke about the performance, we didn't speak much about the result. We said if we put in a performance that we can be proud of the result would like after itself.
"It was obviously really tough conditions out there with the rain and the set piece was so important, and that's where the lads were brilliant."
McGrath played a central role in the victory, with Bulls boss Jake White complimenting him afterwards for a performance that meant that Gibson-Park wasn't missed by Leinster.
The scrum-half's chip through set up Jordie Barrett for the province's second try - and for the All Black's last in a Leinster jersey before his return home.
"He actually said it to me a few minutes before that, when I hit a box kick, he just said it could be on and just listen for me," McGrath said.
"But when he said it, it was quite late and I just thought hopefully he gets to that ball and look, he did and it was a relief to see him go over the line."
McGrath remarked that Leinster's defensive prowess before the break, when they managed to keep the Bulls scoreless, was key to the victory - the province's first in a final in four years.
"Jack (Conan) and Garry (Ringrose) were unbelievable in that five minute block but I think that was the winning of the game there, those sets just to keep them scoreless at half-time was pretty special,
"Jordie and Garry were world class in defence all day."
He also paid tribute to the young guns who were hugely influential, such as Thomas Clarkson at tighthead in the scrum and man of the match Ryan Baird around the pitch.
"It's huge, especially when we've lost a lot of experience in the last few weeks," said McGrath.
"I just think TC has had an incredible last month, and he dealt with disappointment as well but in training he has been top class and I'm so happy for him and for the lads who won their first trophy with Leinster.
"We had a few years there where it was very, very tough, but it's all the sweeter now, seeing everyone's face in there now was pretty special."
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