Champions Glasgow City lost their first Scottish Women's Premier League match in almost six years as a Katie Reilly goal gave Spartans a 1-0 win.
Eddie Wolecki Black's side had not lost since a 2-1 defeat by Celtic in November 2008.
However, despite giving a debut to striker Morgan Marlborough after she arrived on loan from Kansas City, they were beaten by Debbi McCulloch's side.
Rangers narrowed the gap at the top with a 4-1 win away to Hibernian.
Celtic drew 2-2 with Aberdeen, while elsewhere there were wins for Hamilton, Queen's Park and Buchan.
Glasgow City boss Wolecki Black refused to be downhearted after seeing his side's long record come to an end.
"I couldn't be any prouder of them," he said.
"The reason being is that for any club to go almost six years without a league defeat is an incredible achievement and it is a record I am not sure will ever be beaten.
"We will respond, there is no doubt about that and I am more than confident that we will be the champions despite this loss.
"Today it is Spartans' day and we congratulate them on their victory."
Aberdeen 2-2 Celtic
Hibernian 1-4 Rangers
Glasgow City 0-1Spartans
Hamilton Academical 1-0 Forfar Farmington
Queen's Park 3-1Inverness City
Buchan 7-2 Hutchison Vale