Celtic thrash Kilmarnock to win 54th Scottish Premiership title in style
The Hoops only needed a point at Rugby Park, where they had already lost twice this season. But there was never any danger of a repeat of those defeats as goals from Adam Idah, Daizen Maeda and James Forrest put the visitors 3-0 up inside 35 minutes.
Matt O'Riley then struck twice in the second half to round off his outstanding season.
Celtic's 12th title in 13 years moves them to within one of Rangers' record 55 Scottish titles.
However, this was one of the closest run races of that streak as Brendan Rodgers' men blew a seven-point lead early in the season to trail Rangers with 10 games to go.
The return of key players from injury and Rodgers' experience proved key in the run-in as the former Liverpool boss maintained his record of never having lost a league title in two spells as Celtic manager.
Rodgers sprang a surprise in his team selection for the trip to Killie as Idah replaced Kyogo Furuhashi in the only change from Saturday's 2-1 win over Rangers that virtually secured the title.
The decision to start the Irish international proved inspiring as he opened the scoring by tapping home O'Riley's brilliant cross after just five minutes.
Idah's arrival on loan from Norwich in January was criticised at the time for a lack of ambition on the part of the Celtic board. But the 23-year-old has scored eight league goals in 11 appearances to help his side over the line in the title race.
Japanese international Maeda also fired in from close range after a fine team move opened up the Kilmarnock defence.
Idah and Maeda then combined to set up Forrest for a simple finish.
O'Riley claimed a clean sweep of prizes at Celtic's player-of-the-year awards on Sunday and the Danish international fittingly rounded off the scoring.
The 23-year-old rifled into the roof of the net and then coolly picked out the bottom corner to take his tally for the season to 18 goals and 18 assists.
O'Riley could have just two more games to go in his Celtic career as he attracts interest from the likes of Atletico Madrid and Inter Milan.
But he could sign off with another trophy as Celtic aim to complete a double in 10 days' time when the Old Firm face off once more in the Scottish Cup final.