Martin O'Neill guided Celtic to the double as the Scottish champions beat Dunfermline 3-1 in the Scottish Cup final.
Daizen Maeda and Arne Engels netted in a one-sided first half before Neil Lennon's team made a game of it after the interval.
Substitute Kelechi Iheanacho appeared to put the game beyond the William Hill Championship side in the 73rd minute before Josh Cooper pulled one back six minutes later.
It was a ninth consecutive win for Celtic, who have timed their best run of form perfectly after being galvanised by O'Neill for the second time this season.
The 74-year-old now has nine major honours as a Celtic manager stretching over 26 years and, if it is his final game in management, it was a fitting end as he capped a triumphant return to Glasgow against his former Leicester and Hoops midfielder Lennon.
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The goalscoring form of Maeda and Iheanacho has been crucial in the run-in as Celtic pipped Hearts to the title in the closing stages and claimed their 43rd Scottish Cup success.
Maeda has produced nine goals in seven matches, more than he managed in the first eight months of the campaign, and Iheanacho has netted six goals in nine matches off the bench, including the late winner at Dundee that kick-started their run of victories.
O'Neill brought James Forrest into his starting line-up and the winger got the first shot on target on the way to collecting his club-record 28th major winners' medal.
Lennon's tactics appeared to be balls over the top for Callumn Morrison and the forward almost benefited from some hesitation in the Celtic defence as Alistair Johnston tried to shepherd a long ball back to goalkeeper Viljami Sinisalo.
Morrison got his foot in and stabbed the ball towards goal only for Liam Scales to race back and clear off the line.
It was Celtic who took the lead from a long pass in the 19th minute. Tod failed to cut out Alistair Johnston's ball and Maeda lobbed it over the stranded Aston Oxborough.
The champions were in complete control for the rest of the half, passing the ball about with tempo, posing a threat with Maeda's runs in behind, the wing play of Yang Hyun-jun and Forrest, and Kieran Tierney's overlaps.
They doubled their lead in the 36th minute when Engels hit a powerful strike from 25 yards that left Oxborough flat-footed.
Lennon made a triple change at half-time and the Pars looked a different team with Chris Kane and Zak Rudden forming a new strike partnership and Shea Kearney on at right-back.
Nurudeen Abdulai and Kane threatened with headers, Sinisalo clawed away Andrew Tod's lofted effort before another substitute, Alfons Amade, came close from 25 yards.
Iheanacho was denied by an offside flag directed against Yang after he slotted home the South Korean's cutback. But the former Leicester striker delivered the key moment of the half when he latched on to Benjamin Nygren's through ball and showed tremendous footwork to evade three defenders and Oxborough before netting from close range.
Dunfermline gave their fans something to cheer when substitute Cooper scored on the rebound after Charlie Gilmour's shot had been blocked following good work from Rudden.
The Pars kept pushing and Jeremiah Chilokoa-Mullen headed over before Rudden had a shot saved.
There was an injury concern for Scotland manager Steve Clarke when Tierney went down in the wake of the Pars goal but he played on for several minutes before being replaced.
O'Neill refuses to rule out staying on
Following the game, O'Neill refused to rule out extending his return to management.
When asked about his future, the former Republic of Ireland boss said: "If you were asking me, will you start back in a week's time? I genuinely couldn't do that.
"I'll have to have a think. I think in the next week, I'll meet up with the owner [Dermot Desmond], see what he's saying. He hasn't said anything to me, so I don't know whether that's good news or bad news.
"I will genuinely have a wee look at it to see. But I would be thinking that the football club, to go forward, to go forward properly, would probably be looking at somebody younger.
"I would have thought that in the last few weeks they would be looking at options."
O'Neill declared he would never lose the hunger or passion for football but added: "There wouldn't be anybody in this room my age here. So you've got to consider that. Listen, I know I can pass it off as a joke, but I genuinely don't know.
"I would think that I must be in consideration for the job, even though it might only be for a very short term."