Scottish League Cup: Hibernian 3-3 Dundee United (6-7 pens)

• Dundee United through to League Cup semi-finals

• Radoslaw Cierzniak saves two in shoot-out

• David Gray is denied to put United through

• Hibs' six-game unbeaten run is ended

Radoslaw Cierzniak saved two shoot-out penalties to send Dundee United through to the semi-finals of the League Cup.

Having come from behind on three occasions, Hibs were denied victory when Matthew Kennedy failed to convert.

Conor Townsend then made it 7-6 on penalties and Cierzniak pulled off a great diving stop to thwart David Gray.

Chris Erskine, Aiden Connolly and Ryan Dow had netted for United in normal time, with Dominique Malonga, Jason Cummings and Kennedy replying.

John Rankin was the first man to miss from the spot, blazing over after 12 players had found the net from 12 yards, but his anguish soon turned to joy after Cierzniak's heroics.

Both goalkeepers had been busy during an incredible game, with a youthful United side going on to join Aberdeen, Celtic and Rangers in the last four.

Having been denied a derby win by a stoppage-time goal on Sunday, Hibs may be deflated but there were lots of positives for the home side.

Scott Allan was exceptional in midfield and there was spirit in abundance, which has been lacking at Easter Road in recent seasons.

United were first to strike as a fizzing pass from Jon Souttar was expertly laid off by Dow, allowing Erskine to run on to the ball, stab it through the legs of Liam Fontaine and race through to plant a firm shot beyond Mark Oxley from the edge of the penalty area.

Radoslaw Cierzniak is congratulated by team-mate Jon Souttar after his penalty saves

With United temporarily down a man as Gary Mackay-Steven received treatment, Hibs were soon level as Allan threaded a lovely pass through the inside left channel for Malonga to coolly slot into the opposite corner.

And United were still playing with 10 when they regained the lead.

Dow darted in behind the home defence to gather a raking Rankin pass and the ball spun loose with a sliding Oxley getting there at the same time.

The United midfielder was quickly on his feet to square to Connolly right in front of goal only and the 19-year-old took a touch as Lewis Stevenson lunged into a desperate sliding tackle and the ball rattled into the net with the force of the collision.

With the game wide open, Cummings should have levelled when Malonga picked out his strike partner with a smart cross from the left but instead smashed the ball over from near the penalty spot.

Cierzniak then made a superb fingertip save to keep out a Liam Craig free-kick, having earlier stopped shots from the same player and Cummings.

Hibs were fortunate not to concede a penalty when David Robertson appeared to block off Dow and a the first half came to a close with a rising shot from Erskine deflected off target by Fontaine inside the six yard box.

Dominique Malonga scored his sixth goal of the season for Hibernian

The second period was just seconds old when the goal opened up for Craig, but the reinstated Hibs skipper hoofed a shot over from 18 yards.

Gray thought he had equalised when his drilled shot made it through a cluster of players only for Cierzniak to block, with Souttar hacking the ball away.

However, the home fans were soon celebrating when Cummings timed his front-post run to perfection, steering in a header from Stevenson's delivery.

Having done so well to get back into the game, Hibs immediately fell behind again after some sloppy defending.

Paul Hanlon was short with a headed back-pass, putting Oxley under pressure from Dow, but the defender made it back on to the goal-line to clear Erskine's shot after the keeper had stopped an effort from Nadir Ciftci.

A corner followed and Gray made a mess of marking Dow, gifting the midfielder a simple header.

United were now finding holes in the home defence, but Hibs were rewarded for pushing men forward when substitute Kennedy cut in from the left and his deflected shot looped over Cierzniak.

With fatigue and nerves setting in during extra time, the standard of play deteriorated, giving the goalkeepers a well-earned rest before the shoot-out.

The closest thing to a miss in the first 12 penalties came when Oxley swatted Stuart Armstrong's effort against the underside of the crossbar and Cierzniak was soon the man swamped by gleeful team-mates.

Hibernian manager Alan Stubbs: "I've just said to the lads they should be really pleased and that I'm proud of the way they played again.

"We've played really well and we've raised our game in the last couple of months.

"When you go to penalties, it's a lottery and I'm just proud of the ones who stepped up as it's not easy.

"People think taking a penalty is easy, but it takes a lot of courage and it's only easy when it goes in.

"We've gone toe to toe with one of the best teams in the country and come out of it with a lot of credit."

Dundee United manager Jackie McNamara: "First and foremost, give credit to Hibs - I thought it was a fantastic match with both teams going at it.

"I don't think there was much time for breath throughout the whole match and it was a great advert for Scottish football with the amount of young talent on display.

"Obviously Hibs had a chance to win it and there was a fantastic save by Rado - then he pulled off another one to get us through to the next round.

"It is more relief than anything. it was a tiring match and the lads are absolutely drained in the dressing-room, but it is a good feeling to have won it.

"I thought we looked stronger in the first half of extra time, but credit to Hibs, they kept coming at us and it was a fantastic win for us."

John Rankin's penalty miss handed his former club the chance to win but his pain was short-lived