Watch: Celtic players lift the Scottish Premiership trophy
Celtic ended their successful Scottish Premiership defence with an enthralling win against feisty St Mirren before being presented with the league trophy in the Glasgow sunshine.
Matt O'Riley cancelled out Mark O'Hara's opener for St Mirren but O'Hara scored again from the penalty spot after Stephen Welsh had fouled Toyosi Olusanya.
Kyogo Furuhashi struck Celtic level before the break and Luis Palma forced in their late winner.
Brendan Rodgers' side end their league season with 93 points and an eight-point advantage at the top.
St Mirren, in fifth, post a points return of 47 in their second successive season finishing in the top half.
After Welsh almost enhanced the party atmosphere with an early header wide of the St Mirren goal, the visitors took a surprise lead.
Richard Taylor and Olusanya tried to make a clean connection following a long throw-in and O'Hara pounced on Callum McGregor's headed clearance with a powerful low shot past Joe Hart, denied a clean sheet on his final Celtic Park appearance.
O'Riley curved a shot wide of the St Mirren goal as Celtic tried to force a leveller but the midfielder found the net moments later.
The Denmark international played in Kyogo and then lashed in the loose ball after St Mirren's Alex Gogic had intervened.
But the visitors dampened the excitement of the crowd once again.
The ball bounced over Welsh's head and allowed Olusanya to bear down on goal. Welsh bundled him over and the video assistant referee (VAR) supported referee Matthew MacDermid's decision to point to the spot.
O'Hara kept his cool to beat Hart to the keeper's left.
Celtic had it all to do again but the ever reliable Kyogo and Reo Hatate delivered. Kyogo released Hatate on the right and then sped into the box to convert the eventual cross.
Kyogo almost scored from close range again early in the second half, denied by a fine Zach Hemming save, and an equally impressive tackle at the other end by Maik Nawrocki blocked Olusanya's goal-bound shot.
A further Olusanya effort went wide when a pass may have been the better option.
There was one more big chance and it came Celtic's way. O'Riley's backheel set Ralston away on the right and his back-post cross was converted by Palma.
And, before full-time, Hart, having taken over the captaincy from McGregor, was given a standing ovation as he made way for Scott Bain.
Player of the match - Matt O'Riley (Celtic)
The midfielder (right) netted his 19th goal of a fine season and had a hand in the winner
Thrilling end to the season - analysis
Rodgers made six changes to his starting line-up and it's unlikely next Saturday's Scottish Cup final line-up against Rangers will resemble this one.
The manager has relied largely on predecessor Ange Postecoglou's team to get Celtic over the line in the league title race and a similar approach at Hampden would not be a surprise.
St Mirren boss Stephen Robinson spoke pre-match about the need to score during periods of ascendancy and O'Hara delivered on that front.
Defensively, they were put under enormous pressure in the second half and almost held out.
All in all, the entertainment on show was a fitting end to the Premiership season for both the champions and Europe-bound St Mirren.
What they said
Watch: Celtic manager Brendan Rodgers reacts to win over St Mirren
Celtic manager Brendan Rodgers: "Despite all the changes, I thought we played some really, really good football on an extremely hot day and then just to cap it off with getting the goal late on typified the mentality of the team.
"So pleased for everyone. Pleased to have finished the league campaign strong, to have won the title and give a great day to the supporters. Overall, we come out of the game with the three points and a great way to celebrate.
"So, so pleased for [Joe Hart]. His enthusiasm, his leadership never tired. He leaves here next week a legend. It was a lovely day for him."
Watch: St Mirren reacts to defeat by Celtic
St Mirren manager Stephen Robinson: "It's another really good performance against Celtic, arguably the best we've played.
"The second goal's a really poor goal to concede. The third goal's really poor. We just switched off. It just shows how far we've come that perhaps we're disappointed not to get a point."
What's next?
Holders Celtic take on Premiership runners-up Rangers in next Saturday's Scottish Cup final (15:00 BST).
St Mirren's season is at an end and they will enter the Europa Conference League at the second qualifying round stage in late July, with the draw in mid-June.
