Clare netted the equaliser from the penalty spot before Ikpeazu knocked in the clincher in the 77th minute.

Moments later, the big Englishman was forced off with a serious head injury but his goal was to prove decisive.

This encounter was not expected to be anything less than full-blooded and frenetic, and the players did not disappoint from the off.

A late melee earned Dominic Ball, Lewis Ferguson, Arnaud Djoum and John Souttar bookings and betrayed the animosity between the sides.

The visitors drew first blood in the 15th minute, with McLennan heading into an unguarded net after Sam Cosgrove's header to a Niall McGinn corner rebounded off the crossbar.

In an end-to-end game, Aberdeen skipper Graeme Shinnie later flashed a low drive just wide of the left-hand post, while McGinn was forced to deny Jamie Brandon with a superb defensive header.

After finidng themselves under pressure, Aberdeen finished the half in control.

First Cosgrove brought out a superb diving save from Zdenek Zlamal, while a powerful Shinnie drive was punched away by the Hearts keeper.

The frantic proceedings resumed after the break and Hearts should have drew level in the 50th minute, only for Ikpeazu to screw a shot wide after Brandon had challenged Lewis for a high ball.

Hearts did find the equaliser in the 60th minute, with Clare making no mistake from the penalty spot after Andrew Considine had brought down Jake Mulraney.

The Tynecastle players screamed for another spot-kick two minutes later as Ikpeazu latched on to McGinn's short pass-back but referee Joh Beaton ruled the striker dived past Lewis' challenge and instead flashed a yellow card.

The goal, though, had inspired Hearts and Ikpeazu tested Lewis with a powerful drive that was too straight before the Dons keeper saved bravely from an off-balance Craig Wighton.

Aberdeen responded with a McLennan shot that fizzed over the bar but Hearts were in command and they clinched the victory with 13 minutes remaining.

Ikpeazu used his strength to get the better of Considine and Scott McKenna, with his finish exemplary and later resulting in him earning a deserved standing ovation when taken off on a stretcher due to a head knock.

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