Aberdeen continued their recent resurgence under caretaker manager Barry Robson with a thumping 3-0 Scottish Premiership win over Hearts at Pittodrie.
The contest was all but over at the interval, with the Dons three in front thanks to a brace from the impressive Duk and a header from Mattie Pollock.
There were no further goals in the second half, but this was Aberdeen’s fourth win in their last five matches as they moved within four points of their third-placed opponents.
Hearts simply couldn’t cope with the intensity of the home side, which was typified by Graeme Shinnie’s tenacious and action-packed display.
In fact, Shinnie played a big part in Aberdeen’s opening goal on 5 minutes, getting past James Hill and sending a low cross in from the left.
Zander Clark could only parry the ball until Duk, whose 12-yard volley settled into the net with the help of a slight deflection.
The hosts were riotous and it came as no surprise when they doubled their lead on 21 minutes.
A fine run of play near the touchline culminated in Pollock delivering an accurate cross and Duk finding space in the box to blast a header into the far corner.
Pollock then went from provider to scorer in the 28th minute as Hearts’ afternoon showed no sign of abating.
Leighton Clarkson’s free-kick had whip and curl and Pollock, on loan from Watford, headed past the helpless Clark.
However, it could, and probably should have been four soon after, Ylber Ramadani shot wide from 12 yards after running onto Duk’s pass.
The visitors were being split up and in an attempt to stem the flow, boss Robbie Neilson replaced Alex Cochrane with Stephen Kingsley, although it could have been any player in a Jambos shirt given the hook.
Early in the second period, Duk tested Clark with a deflected shot from distance before Robert Snodgrass squandered the chance to get the one back for Hearts when he netted on goal and Lawrence Shankland missed a decent chance.
With Jay Gorter ill, the recovering Kelle Roos was back in goal for Aberdeen for the first time in two months, but his counterpart Clark continued to be busier as he fended off another Duk effort.
The hosts relaxed as time wore on and finished the game with a minimum of fuss to record a third successive home win and climb a place to fourth in the table.
aberdeen return to Scottish Premiership action after international break to Saint John of Stone April 1
hearts journey to Kilmarnock the same day. Both games will begin at 3:00 p.m.