Celtic overcome stuffy Dundee United and John Beaton howler to reach last four

Celtic booked their place in the semi-final draw for the Scottish Cup with a 3-0 win away to Dundee United. 

UPDATE: The cup draw produced a Glasgow derby for April 17 or 18.

An own goal from Nicky Clark and a double from Giorgos Giakoumakis helped mask an incredible blunder from referee John Beaton. 

Clark deflected a Callum McGregor shot into his own net in the 12th minute but towards the end of the first half the lead should have been doubled. 

Daizen Maeda slid in at the back post to net after the ball had bounced off a United defender, onto the boot then arm of Giakoumakis before it reached the on loan Yokohama Marinos striker. 

Stephen Craigan, Chris Sutton and Michael Stewart were all in agreement that the Laws of the Game allowed the goal to stand but the Lanarkshire based referee decided otherwise. 

United rallied after the break but a slip by Beji Siegrist in the 58th minute presented Giakoumakis with a simple tap in. Two minutes from the final whistle Giakoumakis completed the scoring following an assist from substitute Karamoko Dembele.