McInnes made three changes to the side that beat Dundee 1-0 a fortnight ago. Joe Lewis returned to action for the first time since he injured his knee against Rangers in Glasgow two months ago, with Freddie Woodman dropping to the bench. GMS and Greg Stewart also started for The Dons in place of Chidi Nwakali and Niall McGinn.
The opening 10 minutes were fairly uneventful with both sides adjusting to the pitch and the blustery conditions. Having had two weeks rest the Pittodrie surface was slightly improved but still remained challenging to play on, with the ball bouncing and bobbling in all directions as neither side could grasp a foothold in the game.
Greg Stewart had the first half chance of the game, after a nice one-two with GMS. He dug out his shot which was goal bound but well blocked by a St Johnstone defender. The visitors were proving hard to break down, scrapping for everything in midfield but were unable to trouble Joe Lewis in the Aberdeen goal. It was the home side who went close again through Ryan Christie.
On the counter Stevie May was released down the right hand side, May did well to find Christie who had made a good supporting run. Christie shifted the ball on his left and tried to find the far corner but his effort lacked the necessary curl to creep in at the back post.
Murray Davidson received the first caution of the afternoon, booked for a heavy challenge on Graeme Shinnie.
The away side enjoyed a their fair share of possession and territory in the Aberdeen half. Although not creating any clear cut chances they away side did well to stifle any Dons attacks. If a goal was to come it was either going from a St Johnstone ball into the box or an Aberdeen counter attack.
Thankfully for the home side it was the latter and Aberdeen opened the scoring through Ryan Christie. After a quick turnover in possession GMS played a lovely cushioned volley into the path of Christie who found himself bearing down on Alan Mannus in goal. Christie showed excellent composure to shift the ball onto his left foot and go round Mannus. Ryan didn?t fancy it on his right so he checked back inside and back onto his left, teasing the supporters and the St Johnstone defence before calming slotting home into an empty net as the yellow shirts poured back in vain.
The goal gave the home side a much needed lift and the game began to open up.
Stevie May had a two good chances to double Aberdeen's lead. After being set up by GMS, the strikers effort lacked conviction and accuracy to beat Mannus. May then cracked the bar with a header from a Graeme Shinnie cross. The ball cannoned off the underside of the bar and fell to the arriving Christie who's follow up was saved at point blank range by Mannus.
But it was third time lucky for May. With 5 minutes to go before the break the former St Johnstone man got his goal. Christie turned goalscorer to provider, running straight through the middle of the park he slipped in May with a perfectly weighted pass. May made no mistake in converting this time ? calmly stroking a first time right footed shot past Mannus for his fifth goal of the season and his first since November.
The teams came back out for the second half and The Dons looked in the mood to add to their two goal tally.
It only took 6 minutes to add another, courtesy of great work from both full back?s showing their attacking intent by pushing high up the field. Creeping in at the back post Shay Logan met Andy Considine's cross with a diving header. His effort beat Mannus in goal and was heading towards the far corner before Greg Stewart added a final touch, tapping into the empty net to make it 3-0.
St Johnstone made two changes at the break with Chris Millar and Murray Davidson making way for Matty Willock and Blair Alston. Unfortunately for the visitors Alston only managed 8 minutes before being forced to come off after going over his knee in the corner ? Richard Foster replaced him.
McInnes made his first change of the afternoon, after featuring in both of Scotland's international friendlies and with a busy period of fixtures coming up Scott McKenna was given a well deserved rest and replaced by Mark Reynolds.
May won the first of a succession of corners on the hour mark. The best chance came to Logan who got his head on the end of Shinnie's delivery ? the ball looked set for the top corner but Mannus stuck out a hand to deny Logan his goal.
St Johnstone got one back with just over 20 minutes to play from a corner. The Dons defence switched off and St Johnstone played their corner short. Matt Willock's header took a deflection off Stevie May and flew past the helpless Joe Lewis in goal.
GMS was replaced by Dominic Ball as the game entered the final 15 minutes. The Dons still had to be wary of the visitors threat as another goal would?ve made for a nervy finish to the game.
But Greg Stewart put the game beyond all doubt with 9 minutes left to play with the pick of the goals. Stewart finished off a nice flowing move down the left hand side, after a clever flick from Christie, Stewart hammered a left footed half volley into the bottom left corner.
McInnes brought Rooney on for May in the final stages, Considine nearly added a fifth but his effort was cleared off the line and the game finished Aberdeen 4-1 St Johnstone. The Dons now head to Motherwell on Tuesday night.