Linfield have lifted the Gibson Cup for a record-extending 57th time after defeating Glentoran 2-1 at Windsor Park.
David Healy's side had secured the Irish Premiership title in March and, knowing a trophy presentation was to come, could enjoy the occasion against their fierce rivals.
Kirk Millar struck a first-half winner for Linfield after Jordan Jenkins had cancelled out Callumn Morrison's opener for the hosts.
Captain Jamie Mulgrew, himself winning his 11th Irish Premiership title, lifted the Gibson Cup as thousands of Linfield supporters enjoyed the celebrations at a sun-soaked Windsor Park.
"I'm full of adrenaline and emotion, it was a great day," Mulgrew told BBC Sport NI.
"Our performance levels were pretty good and Glentoran made us work for it. All in all, the players and staff have been incredible this year. It's been hugely challenging, but I'm so pleased for them.
"The manner in which we won it this year was incredible. I couldn't be more proud of the players and the staff."
Win icing on the cake before celebrations
It has been a remarkable league campaign for Linfield, who ended Larne's two-year stint as champions in emphatic fashion.
As their rivals faltered, Linfield consistently collected points and became the first team to seal the title before the split - which occurs with five matches remaining.
The victory over Glentoran, who were unbeaten against the Blues this season in five outings, was the icing on the cake.
In a frantic first half, Morrison opened the scoring as he squeezed an effort past Glens goalkeeper Daniel Gyollai in the ninth minute, but Declan Devine's side hit back when Jordan Jenkins fired home in the 22nd minute.
However, Linfield stalwart Millar restored Linfield's lead on the half-hour and the hosts, who spurned chances to extend their lead after the break, never looked back.
Such was their dominance, Linfield's lead at the full-time whistle over Glentoran stood at a mammoth 25 points.
It is a 57th Gibson Cup for Linfield, and no team has won their domestic league more times in world football than the Blues.
It has been an emotional year for Linfield after the loss of staff member Paul Butler and former defender Michael Newberry. Both were honoured as Mulgrew lifted the Gibson Cup with Butler's name - as it has been all season - embroidered into the blue shirt while Newberry also had a Linfield jersey with his name printed on it.
"I'm incredibly proud of the team and the effort they have put in, and the emphatic way we won the league," Mulgrew said.
"At the start of the season we never could have envisaged it would have ended this way. I'm proud of my record of 11 league titles but I'm just really proud and privileged to lead this team."
Mulgrew, 39, added it was "important to put on a show and win" against Glentoran so players, staff and supporters could fully embrace the celebrations.
"It's trophy day and it's important that you win to enjoy the moment even more," he said.
"We want to get as many points as we can to build a platform for next season.
"I'm already looking forward to what we achieve next year, we want to remain hungry and determined after what we have achieved here."
