Callum Hendry’s first-half strike gave St Johnstone a vital 1-0 win over Aberdeen at McDiarmid Park – a result that sees Dundee relegated from the cinch Premiership.
Hendry drilled in a Glenn Middleton cutback for his eighth goal since returning from a loan spell with Kilmarnock in January to ensure the Saints will face Arbroath or Inverness in the play-off.
The win moves them an unassailable six points clear of Mark McGhee’s Dundee with only one game remaining, while Aberdeen stay 10th following a disappointing run of just two wins in 11 games since Jim Goodwin took over in February.
St Johnstone boss Callum Davidson made three changes following his side’s 1-1 draw at Livingston on Saturday. James Brown and Jacob Butterfield came into the starting line-up and Middleton also earning a start after scoring Saints’ goal after coming off the bench at the weekend.
Aberdeen manager Goodwin also opted for three changes, with Michael Ruth coming in for his first start, along with Adam Montgomery and Funso Ojo.
The hosts had the first chance of a cagey opening as Melker Hallberg miscued a shot wide, before the visitors’ Lewis Ferguson missed the target with a headed chance at the back post.
Middleton looked lively from the off following his first league goal of the season against Livi and he was next to come close, fizzing a 25-yard shot just wide following a neat flick from Hendry.
And moments later it was the same pair who combined again for the opening goal in the 17th minute.
Middleton drove to the byline and delivered a low cross to find Hendry, who showed impressive movement to make half a yard and brilliantly divert a first-time shot past a helpless Joe Lewis.
St Johnstone came close to extending their lead within two minutes but Lewis was equal to a free-kick from the impressive Middleton.
Aberdeen struggled to create anything clear cut, with Vicente Besuijen seeing two shots blocked before Connor Barron’s long-range drive whistled narrowly wide of a post following their best move of the match.
Goodwin would have been hoping for a reaction from his players at the start of the second half but it was the hosts who started the brighter.
Shaun Rooney should have made it 2-0 in the 57th minute, missing a free header from a Hallberg corner, while Hendry came close to his second of the evening shortly afterwards as he curled a right-footed shot narrowly over from 20 yards.
Liam Gordon was booked for hauling down Aberdeen substitute Conor McLennan as the visitors – who enjoyed long spells of possession – finally managed to venture into the final third, but Barron could only fire the resulting free-kick tamely into the arms of St Johnstone goalkeeper Zander Clark.
Teenager Liam Harvey was introduced for his Aberdeen debut – one positive for the Dons on a frustrating night – as St Johnstone held on comfortably to confirm their place in the play-off and send Dundee down.