St Johnstone left Aberdeen's Scottish Premiership title hopes in tatters with a dominant 3-0 win at McDiarmid Park.
Derek McInnes' Aberdeen remain eight points shy of Celtic, who face Ross County on Sunday and need two more wins to send off outgoing manager Ronny Deila with their fifth straight league title.
Joe Shaughnessy headed an early corner against the bar and St Johnstone's early pressure told when David Wotherspoon's 14th-minute free-kick evaded Scott Brown in the Aberdeen goal.
It was a blow from which the visitors were never able to recover and, after Steven Anderson had a goal dubiously ruled out for a foul on the end of a corner, Steven MacLean hooked home at the near post.
Barry Robson replaced Aberdeen debutant Michael Rose at half-time but it made little difference as Liam Craig finished stylishly in the 55th minute after Mark Reynolds conceded possession to Graham Cummins.