Harlequins general manager Billy Millard said the newly-crowned Gallagher Premiership champions will celebrate "for a few days and few nights" after they stunned Exeter at Twickenham.
Quins' spectacular 40-38 victory saw them crowned English champions for the first time since 2012.
Wing Louis Lynagh, whose father Michael helped Australia beat England in the World Cup final at the same venue 30 years ago, scored two late tries to secure victory.
Quins saw head of rugby Paul Gustard leave the club in January, and have been under the combined coaching tutelage of Millard, Nick Evans, Adam Jones, Jerry Flannery and Charlie Mulchrone.
They became the first club to finish fourth after the Premiership's regular season and land the title for six years.
And in the past eight days, they scored a total of 83 points in seeing off semi-final rivals Bristol and then defending champions Exeter.
"I think it will be a few nights and few days of celebrations," Millard said.
"For an old man like me, you know how special these are and you have got to roll your sleeves up and dig in, so we will be celebrating long and hard.
"The admiration is huge for these players. They were tired after last weekend and we only got a little bit done this week, so I am extremely proud.
"Maybe it is a fairy-tale to the outside, but there was strong belief from weeks and weeks ago."
And paying tribute to 20-year-old Lynagh, Millard added: "He said to me yesterday that he was going to score a try in the corner where he scored.
"He was immense today, and he has got a massive future. He is his own man, Michael is an amazing dad to him, and he is forging his own reputation."
Quins matched Exeter blow for blow during an unforgettable game, leading by 12 points early in the second half, but Exeter rapidly wiped out that deficit before Quins staged a majestic Lynagh-inspired finale.
Jonny Gray, Alec Hepburn, Sam Simmonds, Ollie Devoto and Stuart Hogg scored tries for Exeter, while Joe Simmonds kicked five conversions and a penalty.
Quins, though, would not go away, as an early penalty try was followed by Lynagh's double and scores for Wilco Louw, Alex Dombrandt and Andre Esterhuizen, with fly-half Marcus Smith, who was also sin-binned, landing four conversions on a day when prop Joe Marler was named man of the match.
Dombrandt said: "The belief in our squad is sky-high. Maybe people on the outside looking in doubted us and didn't give us a chance, but I think that galvanised this group.
"We have got strong characters and great leaders, and we knew that if we put a performance in that we were capable of winning it.
"It was basically just staying calm and sticking to the process, not give away any cheap penalties or give them field position and I thought we did that. Our composure and calmness that we had at the end got us over the line.
"Growing up being a Harlequins supporter, coming to watch the games and players like Danny Care, I never ever thought in my wildest dreams I would play for Quins, let alone win the Premiership, so it is going to take a while to sink in.
"We will enjoy this, we will review it in the off-season and come back with a plan to go back to back."
There was an injury scare for Exeter and the British and Irish Lions, meanwhile, when hooker Luke Cowan-Dickie went off after making a second-half tackle.
A stretcher was called for, but Cowan-Dickie was able to return to his feet and walk off the pitch, being replaced by Jack Yeandle, with Chiefs rugby director Rob Baxter reporting that Cowan-Dickie was "fine".
On the final, Baxter added: "We are very disappointed. We would be more disappointed not to be here I suppose, but if I am honest, it felt a funny game all game.
"We never really took charge, although we did have opportunities, or stopped Harlequins from playing.
"At the sane time, I think it is really important that finals day is about the winners. It has been us, and today it is Harlequins' day. They had that bit more emotion, that little bit you need to make a difference.
"We weren't at our best today. Harlequins won the game and they deserve the plaudits."
