IF Adam Rooney was beginning to feel something of a bit-part player since the arrival of David Goodwillie at Aberdeen then a superb hat trick as his side began their defence of the League Cup with a clinical victory in this third round tie against Livingston dispelled such thinking.

Just as they did in the weekend win over Ross County, the pair, now partners, dismantled their opponents, though it did take them longer than might have been expected.

Nicky Low was introduced to the Aberdeen side for the injured Niall McGinn as Livingston, toiling in the league this season, fielded the side beaten by Raith Rovers last Saturday. Ash Taylor's opener, a back-post header from Willo Flood, may not have unsettled the visitors, but it laid down a marker for what was ahead.

Darren Jamieson, the Livingston goalkeeper, may have been culpable for that goal, yet no more than his defenders and, to their credit, the visitors refused to be rattled by going behind and frequently made their opponents uneasy at the back.

Memories of a League Cup exit to Alloa Athletic at this stage of the competition were still fresh in the minds of those Aberdeen players who competed that night when they were forced into a penalty shoot-out after extra time. There were spells when it appeared possible that the visitors might make the Pittodrie men fight harder for their win than they had to.

Indeed, Scott Brown, making his debut for the home side, had to produce a series of acrobatic stops, which included a spectacular save from Keaghan Jacobs's sizzling strike and two eye-catching shots from Gary Glen and his partner, Jordan White.

The SPFL Championship side continued to fight their corner and were forced to defend as the Aberdeen sought to underline their dominance. Which is what they did with 62 minutes played as David Goodwillie's back-heel into the path of Rooney allowed the latter to blast his shot into the roof of the net, thus averting another Pittodrie shock.

With Ryan Jack injured - he was stretchered-off in the 71st minute, Aberdeen reshuffled their formation which produced more fodder for Rooney and though Myles Hippolyte, on for Robertson just before an hour of play saw his first shot, a low Livingston effort from 18 yards, miss the target by inches, Rooney drilled in his second and rubbed salt in the opposition's wounds in the 75th minute.

The visitors were, by then, overcome. Their forays into the Aberdeen half were rare and they began to toil against a fitter-looking, free-flowing Pittodrie side still smelling blood.

Jonny Hayes's low ball across the area was there for the taking with three minutes remaining and when Rooney stuck out his leg, the resultant toe-poke was good enough to beat Jamieson, surely having the busiest game of his season so far.

Derek McInnes, the Aberdeen manager, was a pleased man after this, although the knee injury to Jack is a concern. "They were causing us problems until Adam got the first of his three goals," he said, "but he produced some top quality finishing and there are few like him in the penalty area."