Meanwhile, the visitors only need to avoid defeat to realistically ensure that they will retain hold of that spot for the remainder of the campaign.
Match preview
Aside from the so-called big three, Kilmarnock have been the best of the rest this campaign, and deserve that tag having lost only three league fixtures since December 6.
Unusually, all three defeats have come at the hands of Rangers, the most recent occurring last weekend as Kilmarnock went down 4-1 at Ibrox.
Although Derek McInnes's side initially took the lead, the 22nd-minute sending off of Joe Wright ultimately cost Kilmarnock, who could not hold out until half time.
That brought an end to a six-game undefeated run in the Scottish Premiership, the streak having helped Kilmarnock establish a six-point advantage over fifth place.
As a result, a place in the second qualifying round of the Europa League is well within their grasp, but with Celtic still on their schedule, McInnes will be keen to get the job done on Saturday.
Realistically, St Mirren have already missed out on a top-four spot. For that to be achieved, they realistically need to win their remaining three matches to have any chance of that feat, as well as hope that Kilmarnock fail to prevail from another game.
With a trip to Celtic on the final day, it would take something remarkable to upset the odds, but a Europa Conference League qualifying spot is still available if they can defend fifth.
A five-game winless streak made that appear considerably in doubt ahead of a trip to sixth-placed Dundee last time out, yet Stephen Robinson's side responded with a potentially-pivotal 3-1 victory.
St Mirren now sit five points ahead of their last opponents with three games left, and with home matches with Kilmarnock and Hearts next on their schedule.
St Mirren Scottish Premiership form:
L
D
L
L
L
W
Kilmarnock Scottish Premiership form:
W
D
W
W
D
L
Team News
Barring any injury issues, Robinson is unlikely to make any changes to his St Mirren XI after they ended their poor run of form.
Keanu Baccus helped tighten things up in the second half, but the Australian midfielder may have to make do with a spot among the replacements.
However, it is a different story for Kilmarnock who have Wright suspended due to his red card and Brad Lyons having been ruled out with a hamstring injury.
Robbie Deas should get the nod at centre-back, while McInnes has revealed that Greg Stewart is back in contention after a hernia operation.
If James Balagizi is passed fit after a knee injury, he is likely to only feature on the substitutes' bench.
St Mirren possible starting lineup:
Hemming; Bolton, Gogic, Fraser; Strain, O'Hara, Boyd-Munce, Tanser; McMenamin, Mandron, Olusanya
Kilmarnock possible starting lineup:
Dennis; Mayo, Findlay, Deas, Ndaba; Armstrong, Donnelly, Polworth, Kennedy; Watkins; Vassell
We say: St Mirren 1-2 Kilmarnock
Although both of these teams have been producing contrasting form of late, we still anticipate a competitive fixture. However, Kilmarnock are the favourites for a reason and they should have enough to edge this contest, perhaps by the odd goal in three.