Leeds United grabbed a last-gasp winner through teenager Jonny Howson to reach the League One play-off final with a 2-0 second leg victory at Carlisle, which saw them progress to Wembley 3-2 on aggregate.

With extra-time looming and 30 seconds of a solitary added minute already played, Howson chose his moment to drive a low shot into the bottom corner and send the visiting fans into raptures.

It was his second goal on the night, the first early on drawing the West Yorkshire club level in the tie.

Leeds had a chance moments after kick-off, striker Jermaine Beckford fed by David Prutton towards the edge of the penalty area; but with one man to beat, he took a heavy touch and the ball ran away from him and through to home goalkeeper Kieren Westwood.

In the eighth minute there was a brief moment of worry for visiting boss Gary McAllister (pictured) when Lubomir Michalik executed a sliding tackle on Carlisle striker Scott Dobie, but referee Alan Wiley waved the appeals away.

Barely two minutes further on, Leeds were in front courtesy of Howson. He played a ball down the left for Dougie Freedman to chase, and the resultant ball in at stomach height was controlled brilliantly and driven past Kieren Westwood from eight yards out, level with the near post.

Beckford, a striker of great reputation and Leeds' top scorer this season, should have done better on 13 minutes when Bradley Johnson found him at the back post. His header was weak, downward and wide of the upright.

The fast Simon Hackney, attacking down the left side for Carlisle, had space to run into but could not find an end product until late in the half when his whipped cross between Michalik and goalkeeper Casper Ankergren was brilliantly dealt with by the centre-half.

The Whites had imposed themselves upon the match unlike in the first leg at Elland Road, where they lost 2-1; but they could not create a clear chance to double their advantage and move ahead overall in the tie, while Carlisle were capable of threatening themselves.

Winger Marc Bridge-Wilkinson underlined that fact before the half-time break, unfortunate not to score when he smashed a half-volley 20 yards from goal, forcing a great save from Dane Ankergren in the Leeds' goal.

In the second period the match remained tight and fairly contested, with barely a hint of a yellow card for either side throughout the 90 minutes. Six minutes into it Cumbrians striker Danny Graham climbed highest to direct a free header straight at Ankergren from 10 yards, the best chance they would have on the night.

The most admirable move of the match came with 20 minutes to play, right-back Frazer Richardson playing the ball inside to Neil Kilkenny whose enterprising movement and pass to Howson created the chance for the impressive Prutton. His strike from close range was blocked by Westwood, solid for John Ward's side all evening.

Freedman used his experience to spin off his marker having played the ball to Beckford - full of ambition but short of quality in this encounter - and struck the return pass at goal from 25 yards, Westwood again making the stop at his near post.

Johnson should have put Leeds ahead when his free header from a corner eight yards out - having risen above right-back David Raven, returning after suspension - struck the near upright and ran out for a goal-kick.

The travelling supporters were sent home in jubilation nonetheless when Freedman squared to Howson 20 yards out, the 19-year-old midfielder picking his spot and driving his strike into the bottom corner, out of the reach of Westwood - breaking the hearts of the Carlisle players who had come so close to automatic promotion and recorded that famous first-leg victory at Elland Road.

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Jonathan Symcox / Eurosport