The SNP "collapsed" behind the Tories to third place in a council by-election on Thursday as Labour won the seat.
The Nationalists lost more than a quarter of their vote in the East Kilbride West ward on South Lanarkshire Council.
Labour candidate Kirsty Williams won the seat after taking 1386 first preference votes. The Tories' Bill Dorrian finished in second on 904 with the SNP's Robert Gillies trailing in third on 778.
Labour won 40.3 per cent of the vote, which was up 13.7 points. The Tories won 26.3 per cent, up 6.3 points while the Nationalists fell 8.3 points to 22.6 per cent.
Williams was elected at the sixth round. The turnout was 25.7 per cent, which was down 25.2 per cent from last year's council election.
Labour shadow Scotland Secretary Ian Murray said: "“Another fantastic gain for labour that underlines the polling progress we are making and the continued electoral collapse of the SNP.
"We will work hard for every single vote as Scottish voters know that’s the way to kick out the Tories and change for Scotland in a better Britain.”
The by-election was called after SNP councillor Ali Salamati stood down because his work has taken him overseas. He was only elected for the first time last year.
The poor result for the SNP comes on the back of another by-election loss in the Bellshill ward of North Lanarkshire council.
That followed the resignation of council leader Jordan Linden as he faced several accusations of sexual harassment.
It means that both council by-elections which Humza Yousaf has faced since becoming SNP leader and First Minister in March have been losses.
It is likely that there will be a Westminster by-election in Rutherglen and Hamilton East later this year as sitting MP Margaret Ferrier is facing a recall petition.
Labour is currently hopeful of winning back the seat which it lost in 2019.
To sign up to the Daily Record Politics newsletter, click here.
