It was a chance to reduce the gap to St Mirren to just two points.
But sorry St Johnstone failed to register a single shot on target in this McDiarmid Park defeat.
Greg Kiltie's opener early in the second half was enough for the Buddies to leave Perth with a very valuable three points.
They now sit eight points clear of 11th-placed Saints, who simply failed to show up for such a big occasion.
The only change from the Dens Park draw saw Dan Cleary dropping out, replaced by Tom Sang.
Sang, who produced an energetic performance off the bench last week, was operating at right wing-back role and that meant Shaun Rooney - like the second half in Dundee - nudged into a more central defensive role.
Saints had started poorly last time out and again, early doors, were the team on the back foot.
And if not for Zander Clark, St Mirren would’ve been ahead with just one minute on the clock.
The Perth goalkeeper stretched out a left arm to superbly deny Alex Grieve from close range. Later in the opening stages Alex Gogic fired inches wide of the post.
There was something for home fans to get excited about in the 22nd minute when Callum Hendry showed off his neat feet to carve out space just inside the box.
He then looked for the far corner but his right-footed attempt was marginally off target.
The work to create the opening was a rare piece of skill in a first half devoid of much quality. Visiting goalkeeper Jak Alnwick had not been called into action once.
That worrying theme continued into the second half and it was no real surprise when the Buddies opened the scoring through Kiltie’s finish from a Grieve cutback.
Cammy MacPherson and Glenn Middleton soon entered the action, replacing Sang and Ali Crawford.
As the clock reached 70 minutes, Saints still hadn’t forced Alnwick into a save.
Theo Bair and Stevie May then entered the action but, still, the Perth side just did not look like scoring.
Goalkeeper Clark even ventured forward for a late corner. He couldn’t find the same magic as last season.
Elsewhere, bottom of the table Dundee lost to Aberdeen and remain five points adrift.
