Kilmarnock will face a relegation play-off to stay in the Scottish Premiership after they lost 2-0 at home to Patrick Thistle and Hamilton Academical won 1-0 at Dundee to secure survival.
Lee Clark's men went into Saturday's action four points behind Hamilton and goals from Steven Lawless and Kris Doolan for Partick condemned them to defeat while ensuring safety for the visitors.
Kilmarnock will now face either Hibernian or Falkirk in the play-off.
Meanwhile, a Carlton Morris strike in the eighth minute proved to be enough for Hamilton to seal their top-flight status for another season.
St Johnstone came from behind to claim a 2-1 away win over Motherwell that all but wraps up fourth place.
Elsewhere, Hearts drew 1-1 with Ross County.
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