Celtic completed an historic fourth consecutive domestic Treble after overcoming Hearts on penalties following their 3-3 draw in the Scottish Cup final on Sunday.
The Hoops have dominated Scottish football in recent times and no other team has won a trophy since 2016.
While they have played three games fewer, Celtic are well behind league leaders Rangers who are 16 points clear at the top.. Hearts, who are top of the second tier, had hopes of an upset.
However, Celtic took an early lead through Ryan Christie on 19 minutes and doubled their advantage thanks to Odsonne Edoard's penalty seven minutes later.
Neil Lennon's side looked set to cruise to the title, but were pegged back by Liam Boyce on 48 minutes before Stephan Kingsley levelled for Hearts on 67 with the last goal in the regular 90 minutes.
Celtic thought they had won it when Leigh Griffiths scored the game's fifth goal in stoppage time of the first half of extra time, but Josh Ginnelly made it 3-3 on 111 minutes.
It went to penalties and it was Celtic who blinked first when Christie saw his effort saved by ex-Hoops goalkeeper Craig Gordon.
However, Hearts failed to capitalise as they missed their next two spot kicks and Kristoffer Ajer stepped up to seal the win 4-3 on penalties.