Alexander Diamond grabbed his first goal for Aberdeen to help extend the club's run to six unbeaten games in the Bank of Scotland Premier League.

The 18-year-old struck in the seventh minute to put the Dons on the way to a 3-1 win over a poor Kilmarnock side.

Midfielder Steve Tosh hit home on the stroke of half-time after Colin Nish had missed a penalty for the visitors when he feebly stroked the ball into the arms of Aberdeen keeper David Preece.

Leigh Hinds secured the three points on the hour before Nish grabbed a consolation eight minutes from time.

But the fortunes of the two goalkeepers could scarcely have been more different at Pittodrie, with Killie's 19-year old Craig Samson enduring a torrid debut in place of the injured Francois Dubourdeau.

The Dons grabbed the initiative and dominated proceedings right from referee Hugh Dallas' first whistle.

Diamond opened his account for the club with a powerful header from six yards out.

The young centre-half positioned himself in front of stand-in goalkeeper Samson and used every inch of his height advantage over Freddie Dindeleux to send Scott Morrison's free-kick into the net.

The Ayrshire side were dealt a double blow in the first half when Greg Shields and Kris Boyd limped off with injuries and were replaced by James Fowler and Martin Hardie.

Killie had offered little in the opening 35 minutes, with Dons goalkeeper Preece a virtual spectator, but he was still alert two minutes later when faced with a penalty.

Markus Heikkinen was sloppy with his challenge on Peter Canero inside the area, leaving referee Dallas with no alternative but to point to the spot.

Former Dunfermline striker Nish stepped up but didn't strike the ball cleanly allowing Preece to dive to his right and palm the effort away.

The missed penalty buoyed Aberdeen and they stretched their lead on the stroke of half-time through industrious midfielder Tosh.

Richard Foster did well down the left and played the ball into Tosh, who had run the extra yards to catch up with the play and he simply looked up before sending a shot across the body of the rookie goalkeeper.

Booth was next to threaten for Aberdeen and the former Scotland international may count himself unlucky not to have found the net with an impressive hook at the back post.

Scott Morrison's corner found Anderson in the area and he managed to flick the ball into the path of Booth, but he sent his shot inches over.

Samson's debut was rapidly becoming one to forget and his afternoon of agony continued on the hour when he was unable to hold onto a Morrison shot and palmed the ball into the path of Hinds.

The ex-Clyde man intelligently followed in on the first effort and got his reward with a simple tap in from four yards.

Nish did reduce the deficit with eight minutes remaining, but the damage was already done and his diving header at the back post was little more than a consolation.

Teams

Aberdeen Preece, Rutkiewicz, Anderson, Diamond, Morrison, Tosh (Sheerin 77), Heikkinen, Clark, Hinds, Booth (Zdrilic 65), Foster (Muirhead 71).

Subs Not Used: Esson, McGuire.

Booked: Clark.

Goals: Diamond 7, Tosh 45, Hinds 60.

Kilmarnock Samson, Shields (Fowler 24), Greer, Dindeleux, Hay, Canero, Locke (Murray 60), McDonald, Fulton, Boyd (Hardie 35), Nish.

Subs Not Used: Smith, Invincibile.

Booked: Greer.

Goals: Nish 82.

Att: 11,698

Ref: H Dallas (Scotland).