A week on from their 5-2 victory over Hearts in the Reserve League, the Young Dons travelled to Oriam to again face their Edinburgh counterparts with a place in the Reserve Cup Final awaiting the winners.
Aberdeen battled through their mini league of Ross County, Falkirk and Celtic while the junior Jambos had seen off the challenges of Hibs, Kilmarnock and Partick Thistle in the competition group stages.
Paul Sheerin was able to call on the services of loan men Sam Roscoe and Ryan Harrington who played at the weekend for Alloa and Montrose respectively, while Jack Mackenzie returned to fill the left-back slot. The Hearts side showed six changes from last week's meeting at Cove.
Conditions were perfect as the game kicked off and the Dons were first to create an opening, Morgan Brown's header from Ryan Harrington's cross drawing a fine save from Hearts keeper Silva.
Aberdeen continued to threaten and forced a couple of corners in quick succession, from the second of which Ethan Ross burst into the box but couldn't find a team-mate in front of goal.
Hearts took the lead on 15 minutes completely against the run of play. A misplaced pass thirty yards from the Aberdeen goal was picked up by Edwards and the Australian midfielder fed the ball through for Smith to slide it past a helpless David Craddock.
The Dons were awarded a spot-kick on 20 minutes when Silva clattered into Dangana on the edge of the area as the striker chased a long ball, the keeper being booked for the challenge. David dusted himself down and expertly sent the ball into the net to tie things up at one apiece.
Edwards and Smith combined well again for the home side on 25 minutes, the forward's shot finding Craddock well positioned to save. The sides looked evenly matched in what was developing into an entertaining tussle.
Hearts came within a whisker of taking the lead on 32 minutes, Wighton's header from Hickey's cross flashing inches wide of the far post.
A swift Dons break saw Dean Campbell and Chris Antoniazzi create a shooting chance for Harrington, but the full-back's shot was blocked at the expense of a corner. Hearts raced to the other end and a last gasp challenge from Jack Mackenzie prevented Smith from hitting the back of the net for a second time.
The home side were now enjoying more possession, but the Dons defence stood firm in the face of increasing pressure. A fine run by Irving ended with the Hearts man firing just over as the clock ticked down towards the interval.
Right on 45 minutes the Dons gifted Hearts a second goal. Mackenzie played a free-kick back to Craddock who mis-kicked the ball straight to Edwards who took full advantage of the error to roll in the home team's second goal.
A disappointing end to a half which had promised much for Aberdeen although Hearts were beginning to dominate proceedings the longer the game went on.
Half time - Hearts 2 Aberdeen 1
Aberdeen forced an early corner in the second half and Roscoe came close after Virtanen flicked on Ross's delivery. Forcing lay by Dangana drove the Dons forward but Ross couldn't get a telling cross in as the Hearts defence retreated.
Hearts had their first shot at goal on 57 minutes, but Wighton's tame effort was easy for Craddock. Moments later the Dons keeper had to produce a save out of the top drawer, flinging himself high to his left to deny Irving's superb volley. A great shot and an even better stop from the Irishman.
A good move down the Dons just after the hour mark left saw Mackenzie pick out the advancing Brown, but Morgan's header lacked the power to trouble Silva.
Craddock saved well from Moore as Hearts looked for a killer third goal, tipping the winger's powerful drive over the bar. Lewis Duncan replaced Antoniazzi as the Dons looked to change things in their favour.
Hearts introduced Henderson for Smith on 72 minutes and the sub had an immediate impact, forcing Craddock to save well after he burrowed his way in from the right. From the resulting corner, the ball found its way to Edwards who scrambled the ball in from six yards to make it 3-1 to the home side.
Ritchie was booked for a foul on Campbell just before the Dons skipper and Sam Roscoe were withdrawn, Luke Turner and Connor Barron coming on.
Hard though they tried, the Dons couldn't make any inroads into the Hearts lead and the game ended on a sour note as Ethan Ross was shown a straight red card after a clash with Hamilton.
So, a second semi-final loss in the space of four days for the Dons, double disappointment for the youngsters.