Match ends, Partick Thistle 1, Kilmarnock 4.
Kilmarnock ensured they will be playing Scottish Premiership football next season with a decisive win at Firhill.
Tope Obadeyi scored either side of half-time against already-safe Partick Thistle.
That brace came after Jamie Hamill had opened the scoring with a penalty rebound and clashed with team-mate Josh Magennis.
Conrad Balatoni headed home a consolation for the Jags before Magennis made the points safe.
Motherwell's defeat by St Mirren means Killie will finish above second bottom and thus avoid a relegation play-off.
The shackles were off Alan Archibald's Thistle side having secured another campaign in the top flight thanks to a run of one defeat in eight.
Killie were desperately trying to preserve 22 years of top-flight football but had been in freefall since Gary Locke took permanent charge in April.
And Thistle began brightly as Belgian defender Frederic Frans and Kallum Higginbotham went close.
But, against the run of play, Killie took the lead when Greg Kiltie was hauled down by Callum Booth just inside the box.
Hamill stepped up and saw his weak effort saved by Scott Fox before slipping home the rebound - Hamill's first goal since scoring for Hearts against Ross County more than a year ago.
That 2014 goal was followed by a red card when he was involved in a fracas with the then County boss Derek Adams.
And Hamill featured in a flashpoint again, this time with team-mate Magennis with the Northern Irishman appearing to headbutt the goalscorer as tensions boiled over.
It was missed by referee John Beaton and his assistant Kylie McMullan.
It did not seem to disrupt Killie, though, as Obadeyi used his head to flash an Alexei Eremenko corner past Fox to double the visitors' advantage before the break.
Thistle dominated the early part of the second half with Lyle Taylor going close from a free-kick.
But Killie grabbed a third from a disputed Eremenko set piece. The Finn curled into the area and Obadeyi met it again with a low header for his second.
Thistle were not done though and skipper Balatoni headed home a Higginbotham corner to reduce the arrears.
But Eremenko - who received a standing ovation from the boisterous Killie support when subbed - set up Magennis to slip the ball through the legs of Fox to seal a massive win for Kilmarnock.
- 5BoothBooked at 24minsSubstituted forElliottat 45'minutes
- 22FraserSubstituted forCraigenat 77'minutes
- 11LawlessBooked at 39mins
- 15HigginbothamBooked at 78mins
- 29TaylorSubstituted forWilsonat 67'minutes
- 6ConnollyBooked at 20mins
- 29PascaliSubstituted forAshcroftat 45'minutes
- 30KiltieSubstituted forMcKenzieat 73'minutes
- 16ObadeyiBooked at 37mins
- 20EremenkoSubstituted forO'Haraat 86'minutes
- John Beaton
- Shots on Target
Second Half ends, Partick Thistle 1, Kilmarnock 4.
Substitution, Kilmarnock. Mark O'Hara replaces Alexei Eremenko.
Attempt missed. Josh Magennis (Kilmarnock) right footed shot from the right side of the box is close, but misses to the right.
Corner, Kilmarnock. Conceded by Scott Fox.
Kallum Higginbotham (Partick Thistle) is shown the yellow card.
Attempt saved. Josh Magennis (Kilmarnock) right footed shot from the left side of the box is saved in the centre of the goal.
Substitution, Partick Thistle. James Craigen replaces Gary Fraser.
Attempt missed. David Wilson (Partick Thistle) left footed shot from the centre of the box is close, but misses to the left.
Substitution, Kilmarnock. Rory McKenzie replaces Greg Kiltie.
Goal! Partick Thistle 1, Kilmarnock 4. Josh Magennis (Kilmarnock) right footed shot from the right side of the box to the bottom right corner.
Goal! Partick Thistle 1, Kilmarnock 3. Conrad Balatoni (Partick Thistle) header from the centre of the box to the bottom right corner. Assisted by Kallum Higginbotham with a cross following a corner.
Corner, Partick Thistle. Conceded by Craig Slater.
Substitution, Partick Thistle. David Wilson replaces Lyle Taylor.
Goal! Partick Thistle 0, Kilmarnock 3. Tope Obadeyi (Kilmarnock) right footed shot from the centre of the box to the bottom right corner.
Attempt missed. Lyle Taylor (Partick Thistle) right footed shot from outside the box is close, but misses to the left from a direct free kick.
Stuart Bannigan (Partick Thistle) wins a free kick in the attacking half.
Foul by Mark Connolly (Kilmarnock).
Kris Doolan (Partick Thistle) wins a free kick in the defensive half.
Foul by Craig Slater (Kilmarnock).