And after 10 minutes Stevie May, the former Saint, flashed a low effort tantalisingly across the face of goal.

But the best chance fell to the visitors after 25 minutes. Richard Foster, also playing against his former club, played in Matty Kennedy in the inside-right channel and the former Everton winger struck a powerful half-volley that Joe Lewis had to push over the bar.

Saints goalkeeper Zander Clark was tested just before the break as a May corner was headed goalward by Scott McKenna. Clark was left scrambling but managed to scoop the ball clear of danger.

Both sides had claims for a spot-kick in the opening moments of the second half and while Lewis Ferguson's claim for Aberdeen would have been of the soft variety, Tommy Wright's side perhaps had more of a shout after Ross Callachan was challenged by Shay Logan.

Clark was still the busier of the two keepers, though, and he was called into action to deal with a low McLennan strike after 56 minutes but was more than comfortable in doing so.

And just after the hour, he had to get down to his left to push away a Ferguson strike after tenacious work from Lowe created the opening for the 19-year-old.

But it was the visitors who broke the deadlock. Andrew Considine's slip allowed David Wotherspoon to play in substitute Alston and he forced a save from Lewis. From the resultant corner, Shaughnessy rose highest at the back post to head in Wotherspoon's delivery.

And three minutes later, they doubled their advantage in some style as Alston found the top right corner of the net with a superb curling strike from just inside the area.

With 10 minutes remaining, Dons substitute Niall McGinn warmed the fingertips of Clark who pushed his 25-yard free-kick over the bar when it seemed destined for the top corner.

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