Celtic were crowned Scottish Premier League champions this afternoon after beating bottom club St Mirren 1-0 at Parkhead in coach Martin O'Neill's first season at the club.
Tommy Johnson's goal seven minutes before half time secured victory and earned Celtic only their second league triumph in 13 years.
Celtic's Premier League title win is the quickest in the season since Rangers won the league early in 1975.
The runaway leaders made hard work of beating the basement club but few in the capacity home crowd were bothered as Celtic won their 37th championship with a month of the season left.
Celtic's triumph leaves them on course to land the 'Treble'. They have already won the League Cup and are in the semi-finals of the Scottish Cup.
After incessant pressure on the visitors' goal, Celtic edged in front after 38 minutes.
Larsson unselfishly set up the unmarked Johnson in the penalty box and although his first touch was not good, he recovered to slot the ball under Saints French goalkeeper Ludovic Roy.
Defender Scott Walker tried to prevent the ball crossing the line but only succeeded in deflecting the ball into the back of the net.
Although the match was scrappy, O'Neill was delighted with the result.
"It's been a fantastic day. It's all been worthwhile now," he said.
"There was a bit of tension in the dressing room beforehand with all the build-up and the expectation.
"It's been worth waiting for. We got the all-important goal today to win it in front of our own fans.
"I would like to thank the supporters for their massive support, and we could not have won this without the players."
Goalscorer Johnson said: "It's been brilliant. It doesn't matter who scored, we just had to win and we won. It's incredible."