Last week’s 4-0 margin was reversed as Airdrie were on the receiving end of the same scoreline at the hands of table-toppers St Johnstone.

With last week’s result in Dingwall already firmly in the past, the Diamonds failed to increase their advantage over the Staggies, who had lost at Queen’s Park last night.

Aaron Taylor-Sinclair made one change to his line-up, with Sean McGinty replacing Dom Thomas as the head coach moved to a back five in an attempt to turn the tables on a St Johnstone side who had won the season’s previous three meetings.

However, Simo Valakari’s side showed why they have led the Championship table since matchday one with an excellent first-half display, attacking from the off with the league’s top scorer James McPake curling wide inside four minutes.

Harry Stone got behind McPake’s second attempt a minute later, and the keeper plucked a ninth-minute cross out of the air as the Hearts-bound forward threatened again.

Jack Baird led with the elbow as he clattered into Lewis Strapp on 11 minutes, referee Grant Irvine deciding a yellow card was sufficient for the Saints defender.

As Airdrie rallied, McGinty saw a 12th-minute cross headed behind for a corner before Cole McKinnon was denied a shooting opportunity by a flying Jason Holt block.

The hosts won a soft free-kick on 15 minutes when Jamie Gullan went down under minimal contact from Jamie Barjonas, and Ruari Paton opened the scoring with a well-struck setpiece.

Strapp led the Airdrie attack two minutes later, but Toby Steward was out to smother the ball at Chris Mochrie’s feet.

Barjonas saw a strike deflected wide midway through the half, with Sam Stanton suffering the same fate at the other end on 25 minutes, Cheick Diabate heading well over from the resultant corner.

Charlie Telfer’s free-kick was held by Steward before McPake sent an angled shot over the top either side of the half-hour mark.

St Johnstone should have doubled their lead on 33 minutes, Strapp doing well to force behind after a McPake cross had fizzed across the face of goal.

Although the corner was initially cleared, the returned ball into the box was pitched perfectly for defender Morgan Boyes to head home from close range.

Things went from bad to worse for Airdrie a minute later, an incisive St Johnstone move leaving Paton with an easy finish for his second and the Saints’ third.

The shell-shocked Diamonds were lucky not to concede again as Stanton and Liam Smith both sent efforts over the top as half-time approached.

Gavin Gallagher replaced McGinty at the break as Airdrie reverted to a back four, and it yielded some early results as Mochrie almost got in on goal after picking Diabate’s pocket, but the defender’s blushes were spared by his team-mates who swarmed round the Airdrie man to avert the danger.

Gallagher saw a 50th-minute shot charged down, and Diabate hacked Euan Henderson’s cutback out of Mochrie’s path five minutes later.

The home side took control again just before the hour mark, Gullan sending a shot wide from the edge of the box before Holt’s strike was well blocked.

Stone denied McPake before Airdrie rang the changes on 66 minutes, Rhys Armstrong, Robbie Mahon and Owen Stirton replacing Barjonas, Henderson and Mochrie, with Lewis McGrattan coming on for McKinnon six minutes later.

Strapp’s 74th-minute penalty claims fell on deaf ears after a push by Diabate, but there was no such denial at the other end six minutes later, Craig Ross tripping Stanton and Grant Irvine pointing to the spot.

McPake tucked away the penalty with aplomb to make it 4-0 to the hosts.

Stanton sent an audacious half-volley just over the top a minute later, and Stone made a good save from Saints sub Kai Fotheringham with four minutes remaining.

There was no further action to speak of, and Airdrie headed back down the M90 to face a quick turnaround before Tuesday evening’s rearranged meeting with Dunfermline Athletic.