Swansea City's hopes of a dream date at Wembley were ended in the cruellest of ways as the MK Dons won a tense penalty shoot out at stadium:mk in the Johnstone's Paint Trophy area final.
Jason Scotland had lgiven Swansea a 1-0 win with a first-half penalty after Andy Robinson had been brought down by Keith Andrews.
But with the aggregate scores level at 1-1 at the end of normal time, Scotland was the unlucky one to miss his penalty as former Swans 'keeper Williy Gueret made the crucial save.
MK Dons:
Gueret, Lewington, Andrews (c), Diallo, O'Hanlon, Gallen, Cameron, Dyer, Navarro, Johnson, Swailes. Subs: Stirling, Broughton, Carbon, Abbey, Baldock.Swansea City: de Vries, Rangel, Painter, Tate, Monk ©, Robinson, Pratley, Way, Butler, Scotland, Brandy. Subs: Austin, O'Leary, Duffy, MacDonald, Knight.
Ref: Andy D'Urso
Swansea were without midfield duo Ferrie Bodde (shoulder) and Leon Britton (calf) after failing fitness tests for this Johnstone's Paint Trophy southern area final second-leg.
But fellow midfielder Darren Pratley came back after missing the 1-0 first-leg defeat to partner Darren Way in the middle of the park as manager Roberto Martinez started with a 4-4-2 formation.
Top scorer Jason Scotland led the attack alongside Manchester United loan signing Febian Brandy.
Dons manager Paul Ince recalled Colin Cameron to the starting line-up to play in the hole behind striker Kevin Gallen with Jemal Johnson, with Lloyd Dyer out wide. After returning from a loan spell with Wrexham, Drewe Broughton was a surprise inclusion on the bench.
Swansea made a positive start, getting the ball down and playing at a quick tempo in search of the goal that would bring them level on aggregate.
Andy Robinson tried his luck from long range after 14 minutes, but former Swans 'keeper Willy Gueret was down well to save.
Swansea were forced into an early reshuffle though as Marcos Painter limped off after just 17 minutes to be replaced at left-back by the experienced Kevin Austin.
And two minutes later Austin was celebrating with his team-mates as the Swans took an early lead.
Robinson started the move when he combined well with Scotland on the edge of the area. Scotland returned the pass and Robinson was brought down inside the area by skipper Keith Andrews.
Referee Andy D'Urso pointed straight to the spot and Jason Scotland stepped up to coolly slot home his 19th goal of the season.
The Dons responded in a positive manner as they enjoyed a good spell with Kevin Gallon forcing Dorus de Vries into a comfortable save, before skipper Garry Monk made a good block to deny first-leg goal scorer Jemal Johnson.
Tom Butler and Dons Keith Andrews were booked in separate incidents as Swansea were being forced back on their heels for long spells as the home side pushed hard for the equaliser.
But Swansea were defending well as they looked to take their lead in at the interval, before finishing strongly before the first-half came to a close.
Half-time: Dons 0 Swans 1 (agg: 1-1)
Swansea created the first chance of the second-half after just two minutes when Scotland played a superb ball through for Brandy to chase. But, as in the first-leg, Gueret pulled off a great save as the Swans missed a good chance to extend their lead.
Brandy showed neat skills in the 50th minute inside the area before going down under a challenge from Swailes. This time though the referee turned down the penalty appeals.
At the other end, de Vries had to be alert from a Lewington free-kick, diving bravely at the feet of Gallen three yards out.
Brandy became the second Swansea player to be booked for kicking the ball away.
Dons were playing some nice football at that stage as de Vries was forced to pull off a good save from Lloyd Dyer as the home side applied the pressure on the hour.
Swansea's second change came after 65 minutes as Butler, who was lucky to escape a second yellow card, was replaced by young Shaun MacDonald.
Dons were enjoying the better of the possession as Swansea gave the ball away in the 67th minute and nearly paid the price as the home side broke quickly.
The ball was worked wide to Dyer on the edge of the area, but de Vries pulled off a fantastic reflex save as Dyer's shot was deflected of Austin.
Then Alan Tate had to time his tackle to perfection as Gallen broke clear inside the area; again the referee waving away the penalty appeals.
Having weathered the storm, Swansea hit back as Scotland played the overlapping Angel Rangel through; but the Spaniard shot tamely at Gueret with 71 minutes gone.
Scotland was again in the thick of the action as he pulled a ball back from the by-line, but Robinson's shot was deflected behind for a corner.
Robinson delivered it and MacDonald lost his marker inside the area, but the Welsh Under-21 international lost his footing and fired a great chance over.
With 10 minutes remaining Brandy, who had had an impressive game, was replaced by striker Darryl Duffy.
The Dons responded by replacing Cameron with Sterling.
The game remained wide open as the Dons were finishing the stronger of the two sides; piling the pressure on.
But Swansea's defence, outstanding throughout, remained rock solid as Gallen missed a great chance with a header that went wide in injury time.
Scotland nearly created a last gasp winner for the Swans with a great run from deep, but his pull back just failed to find Duffy as the game went to penalties.
Swansea took the first with Robinson scoring. Andrews responded for Dons
Skipper Monk put Swansea 2-1 up with another great penalty, but Dyer replied.
Scotland stepped up with Swansea's third, but Gueret saved. Gallen gave Dons the advantage.
Rangel kept Swansea in it by scoring Swansea's fourth, but Sterling maintained Dons 4-3 lead.
Duffy levelled, but Broughton fired home to send MK Dons through to a Wembley final.
