Celtic 0-0 Dundee United (Celtic win 11-10 on pens). The lights are on at Hampden Park on the south side of Glasgow for the semi-final

Celtic's talented midfielder Shunsuke Nakamura fires a shot past United captain Lee Wilkie

Lukasz Zaluska saves from Celtic striker Scott McDonald, who gets a touch despite the presence of United's Lee Wilkie (right)

Celtic target Willo Flood goes to ground as he tries to dispossess winger Aiden McGeady

Neither side can break the deadlock as Scott McDonald slides in on the Tangerines' Paul Dixon

It's 0-0 after extra-time. Incredibly, both sides score their first eight penalties in the shoot-out. All outfield players have taken their spot-kicks so it's down to keepers Artur Boruc and Lukasz Zaluska

Polish goalkeeper Artur Boruc coolly slots his penalty past countryman Lukasz Zaluska to make it 10-10, after the United keeper, who will join Celtic in the summer, had scored from the spot

The tension is unbearable as Willo Flood takes his second penalty of the shoot-out, attempting to put United 11-10 ahead...

Heartbreak for Flood, who had a terrific match, as his spot-kick clips the bar and sails over

Scott McDonald (second left) scores the winning penalty after Flood's miss and celebrates with his team-mates. Incredible stuff!