Kirsty Howat netted twice in a rampant first half from the Light Blues, bookending Tessel Middag’s volley, before Liv McLoughlin rounded off the scoring in the second period.
However, it wasn’t enough for the Light Blues to be crowned champions given results elsewhere, despite losing just twice across a long and gruelling league campaign.
All eyes will now turn towards next weekend’s Scottish Cup final at the national stadium as Jo Potter’s side look to add their second piece of silverware this season following their Viaplay Cup success in March.
The contest in Lanarkshire started with Rangers looking to settle a score, propelled by the direct running of Mia McAulay on the right-hand side who hit the byline and centred deliciously into Rio Hardy, but the forward was unable to sort her feet out from six yards to direct her finish towards goal.
And they didn’t have to wait too long to make the breakthrough on the afternoon as the in-form Howat, fresh off a midweek hat-trick away to Hibernian, showed her poise in front of goal.
It was Middag who was the architect on this occasion, lifting a gorgeous pass over the top of the Thistle backline where Howat sprung the offside trap and arrowed a driven effort across goal that contained too much power for the diving Ava Easdon to thwart.
The Gers thought they had doubled their advantage just four minutes later when a wicked free-kick delivery from Lizzie Arnot was glanced into the bottom corner by the head of Kathy Hill, but the linesman swiftly raised his offside flag to halt the home side’s celebrations.
Indeed, McAulay was wreaking havoc with her one-on-one ability on the right touchline, breezing past her marker once again on 20 minutes and pulling the ball across to Howat whose first-time flick was parried around for a corner through impressive reactions from Easdon.
However, the 17-year-old ought to have done better when she was liberated into space by Howat moments later as she fired over under little pressure from 15 yards out.
Yet it would matter little as the Gers stretched their lead five minutes later; Middag guiding a sumptuous half-volley on her unfavoured left side into the far corner after the ball bounced kindly to the Dutch defender from a corner.
Lizzie Arnot was very close to adding a third for the Gers when her header was cleared off the line, before Liv McLoughlin swept over from inside the penalty area when she was teed up smartly from a McAulay pull-back.
It was certainly dominance with insufficient reward for Potter’s side, but a third goal arrived moments later when the dangerous Arnot lofted a sumptuous delivery towards the back post from the left-hand side where Howat ghosted in and stabbed a volley beyond Easdon from close range.
Half-time prompted a double switch as Jane Ross and Sarah Ewens replaced Maclean and Hardy at the break, with the hosts looking for much of the same ____ in the second period.
Three very nearly became four just shy of the hour-mark when another dangerous delivery from Arnot was almost met by Ewens and, when the ball arrived towards Ross, the Scotland international just couldn’t quite produce the connection at full stretch.
However, the fourth goal of the afternoon was engineered just two minutes later as McLoughlin slammed home a slick move involving both Howat and Ewens inside the penalty area.
Late drama elsewhere meant the SWPL trophy would not be making its way through to Cumbernauld, although Potter will quickly move her side’s attentions towards the Scottish Cup final in seven days’ time.
RANGERS: Esson, Docherty, Hill (Austin, 59; Martinez, 75), Middag, Howat (McLeary, 80), Hardy (Ewens, 45), McAulay, Arnot (Hay, 59), Cornet, Maclean (Ross, 45), McLoughlin
Subs not used: Fife, Bance
PARTICK THISTLE: Easdon, Slater, Lawton, Falconer, Hay (Donaldson, 33), Henderson (Adams, 80), Bulloch (Anderson. 59), Taylor, Cowan (Docherty, 45), McQuillan (McAllister, 45), Sinclair (Boyce, 45)
Subs not used: Wright, Robinson