Motherwell move three points behind seventh-placed Aberdeen.
Sixteen-year-old Laura Berry scored two penalties as Motherwell saw off Spartans in the SWPL.
The Rangers loanee's first spot-kick was quickly cancelled out by a leveller from the visitors' Hannah Jordan.
Louisa Boyes restored the home advantage with a curling effort from the edge of the box, before Berry stepped up to dispatch again on the stroke of half time.
Spartans gave themselves a lifeline when Alana Marshall pulled one back, but Kayla Jardine immediately restored the advantage.
Victory leaves Motherwell three points off seventh-placed Aberdeen, while Spartans stay 10th, seven points clear of the bottom two.
