St Johnstone were beaten 2-1 at St Mirren in their last outing last Wednesday and they made four changes to that starting XI with Thomas Sang, Tony Gallacher, Murray Davidson and Cammy MacPherson missing out. In came James Brown, Callum Booth, Jacob Butterfield and Melker Hallberg.
It was a grim start for the Dons as Saints went ahead on six minutes. Jonny Hayes appeared to be fouled on the left but Middleton was allowed to run on. He cut inside and fired in a low shot that Lewis saved at full stretch. Crawford was first into the loose ball but somehow Lewis, prone on the ground, saved again, but from that rebound, Hendry was able to tuck the ball away.
Aberdeen responded on eight minutes, Hayes'header from a Calvin Ramsay criss forcing a fine save from Clark. The ball flew clear to Barron coming onto it, but he wasn't able to get the right direction on his effort at goal and it flew away wide.
Moments later, a St Johnstone clearance dropped nicely for Scott Brown who unleashed a thunderbolt from 25 years that Clark was just able to tip onto the bar.
Hayes was next to force Clark into action. Barron, enjoying an impressive first start, played in a cross from the right, Hayes showing lovely control to turn away from a defender and crack a shot goalwards in one movement, Clark saving acrobatically.
On 33 minutes, Clark came out to the edge of the box to collect a routine ball forward and then crumpled to the turf. He took some lengthy treatment to what looked like a calf injury before continuing.
Middleton got in behind on the Aberdeen left again on 37 minutes to unleash a dangerous cross, David Bates cutting it out, Lewis then coming out to claim the corner.
For all his injury, Clark was still mobile enough to get down to his near post to shovel a deflected shot from Lewis Ferguson behind for a corner a couple of minutes later.
Good possession for Aberdeen got Hayes into space on 41 minutes, working the ball back to Barron who curled a terrific shot from 20 yards that was just a foot away from goal. Clark hurled himself at it, got nowhere near it, but as he fell to ground, that was his race run. Parish replaced him.
Christian Ramirez was next to have a go from distance, the ball sitting up nicely for him 25 yards, but he got his angles fractionally wrong and the ball went wide.
Four minutes into added time, Ferguson nearly ended things on a high, drifting inside to play a one-two with Ramirez before firing off a vicious, swerving drive that Parish handled well.
HALF-TIME: ABERDEEN 0 ST JOHNSTONE 1
Besuijen replaced Declan Gallagher at the break in Barry Robson's first change of the game, Brown going back to centre-half. Seven minutes into the half, Montgomery came on for MacKenzie as Aberdeen looked for the breakthrough. Montgomery was swiftly flattened by Cleary, who went into the book as a result, before needing treatment himself.
Ramirez had the first real shot of the half from the corner of the box on 56 minutes, Parish down well to smother. St Johnstone responded with Brown on the break, Bates collecting a card for ending his run. Butterfield then did likewise to Besuijen on 59 and was also booked.
May came on for the injured Hendry in the aftermath. Scott Brown was next to fall to the turf with what appeared to be a hamstring problem and he made way for Funso Ojo on 65 minutes, Ferguson now moving to centre-half.
Against the massed ranks of blue shirts, all behind the ball, space was at a premium, but a clever turn from Ramsay found enough of it to wriggle into the box, where Booth brought him down to give the Dons a penalty. Up stepped Ferguson and he was deadly again, driving it into the corner to level things up on 71 minutes.
That was the signal for Jay Emmanuel-Thomas to be Aberdeen's fourth change, replacing Kennedy on 74 minutes. Gallacher and Craig replaced Hallberg and Booth for St Johnstone at the same time.
The Dons were denied a goal on 78 minutes, Hayes drilling a ball through the penalty area, Ramirez just offside as he drove the ball at goal, Paris saving well but Besuijen lashing in the rebound, all for nothing. It was, however, indicative of growing momentum for the Dons.
It did always mean they were open on the break and Middleton went charging forward on 84 minutes, Bates coming across to make a crucial block to put the shot behind.
Aberdeen had most of the ball and kept probing away, but with every one of the visitors behind the ball, they were banging their heads against a brick wall. Two minutes into added time, Ramsay flashed in a great cross to the back post but Ferguson couldn't quite get over the ball and put his header wide of goal.
In the final seconds, a corner. Ramsay's ball to the back post was headed goalwards by Ferguson, Ramirez coming onto it at a tight angle at the back post, his powerful header clawed away by Parish to ensure the draw.