St Johnstone secured bragging rights and all three points after coming from behind to beat Dundee United at Tannadice.
The result also means that the Tangerines are now six points adrift at the bottom of the Premiership table.
Chances were few and far between in the first half hour but United took the lead in the 32nd minute with a well-worked goal when Ryan McGowan played a one-two with Blair Spittal down the right before crossing for Billy Mckay to head past Alan Mannus in the Saints goal.
St Johnstone looked to hit back straight away and skipper Dave Mackay’s 20-yard free-kick cannoned off the inside of Michal Szromnik’s right-hand post.
However, in the 43rd minute, Saints’ David Wotherspoon swung a corner in from the right with striker Chris Kane powering a header into the net to equalise.
Then just two minutes later, there was an almighty scramble in the United box with Saints hitting the woodwork before Murray Davidson finally bundled the ball home to give Tommy Wright’s side the lead.
In the 52nd minute, United felt they should have had a penalty when McGowan tumbled in the Saints penalty area but referee Craig Thomson was far from convinced and booked the Tangerines player for diving.
However, 14 minutes later, the official was in no doubt that Saints deserved a penalty when Kane went down under a clumsy John Rankin challenge. The normally clinical Steven MacLean stepped up to take the spot-kick but he blasted the ball wildly over the United bar.
St Johnstone continued to look dangerous but United came close to equalising in the 80th minute when a Paul Dixon shot was deflected just over Mannus’s crossbar.
Then just as the game entered extra time, Spittal hit a fierce long-range shot which Mannus acrobatically tipped over his bar to ensure Saints held on to win.
For full report, reaction and analysis, see Monday’s Courier.