A second-half Adam Rooney hat-trick ensured Aberdeen began their League Cup defence with a comprehensive 4-0 win over Livingston at Pittodrie.

Ash Taylor headed the Dons in front in the eighth minute.

Nicky Low found Willo Flood with a short corner and the Irishman's deep cross was converted by Taylor, who rose at the back post to nod home.

Derek McInnes' men took control after the break and doubled their lead in the 61st minute when Rooney hit a 14-yard shot which flew into the roof of the net.

He netted again in the 74th minute, finding space at the back post to beat Livi keeper Darren Jamieson with a clinical finish.

The striker was not finished and made sure he went home with the match ball by tapping home from close range after impressive wing work from John Hayes.

Brian Graham's second-half strike was enough to give St Johnstone a 1-0 win over Kilmarnock at Rugby Park. After a goalless and mostly tepid first-half, St Johnstone came out after the break fired up and in the 54th minute, Graham notched his third goal in four games since arriving on loan from Dundee United

Ross County's miserable start to the season continued when they were bundled out of the League Cup by a Hibernian side inspired by Frenchman Dominique Malonga, who netted with two close-range headers in the first half to give the Hibees a 2-0 win.

The Easter Road side were reduced to 10 men in the 82nd minute when Dylan McGeouch lunged into Joe Cardle - but they held on to book their place in the quarter-finals.