Ten man Leyton Orient stunned Yeovil Town with a late David Mooney header taking them just one step away from Wembley in the Johnstone's Paint Trophy after a dramatic 1-0 win.
Orient looked up against it when Anthony Griffith was dismissed for a second bookable offence in the second half and the match was heading towards a penalty shootout.
But the O's struck in the 90th minute through top scorer Mooney which fired them through to the southern area final next month.
Russell Slade made three changes from the side which drew at Hull City at the weekend. Scott Cuthbert and Gary Sawyer came into the defence in place of Leon McSweeney and Lee Cook.
Griffith also started with Martin Rowlands left out and Moses Odubajo slotted into the midfield with Cuthbert at right back.
The hosts had an early opportunity when Dean Cox sent in a free-kick but Mathieu Baudry was unable to direct it on target.
The O's made a promising start to the tie and midfielder Lloyd James launched an ambitious strike which floated wide of the visitors' post.
Ed Upson had Yeovil's first attempt on goal but his effort was straight into the arms of Jamie Jones.
Yeovil came so close to taking the lead after 27 minutes when the ball fell to Dominic Blizzard and his volley was brilliantly turned round the post by Jones.
The visitors created another chance when skipper Jamie McAlister headed towards goal but it was comfortably held by the O's keeper.
Orient threatened from Cox's corner but Ben Chorley's header was saved by Marek Stech.
The hosts created the first chance of the second half when Griffith set up Odubajo but the teenager blasted his shot over the crossbar.
Odubajo stung the fingertips of Stech from a long-range strike as the O's set the pace after the restart.
Slade's side suffered a major setback on the hour mark when Kevin Lisbie pulled up with a hamstring injury and was replaced by Michael Symes.
Gavin Williams spotted Jones off his line and struck a bold strike from long range which just flew past the post.
Orient came close when Symes set up Odubajo who brilliantly cut inside but his powerful strike was turned over by Stech.
Yeovil earned a free-kick in a decent opportunity outside the box but McAlister's strike flew wide of the target.
The hosts made their second change as they pushed for a winner when Cook was introduced in place of Sawyer.
Orient were reduced to ten men 14 minutes from time when Griffith stupidly received a second yellow card. The midfielder had been cautioned just minutes earlier for a foul and he was dismissed for kicking the ball away.
The visitors had a late opportunity when Blizzard headed towards goal but his effort was too close to Jones.
Just as the match was heading for penalties Orient stunned Yeovil with an 90th minute goal. Cuthbert sent in the cross and Mooney headed the ball home to send the O's fans wild.
There were six minutes of injury time but it was the home side who came closest to adding another when a breakaway saw Cook smash a fierce strike against the crossbar.
The O's held out and celebrated a dramatic victory with the side just two games away from a potential trip to Wembley in the Football League Trophy.
Leyton Orient: Jones; Sawyer (Cook, 73), Chorley, Cuthbert, Baudry; Cox, Odubajo, James, Griffith; Lisbie (Symes, 61), Mooney
Subs not used: McSweeney, Smith, Allsop
Yeovil Town: Stech; Ayling, McAlister, Hinds, Webster; Burn, Blizzard, Upson (Dolan, 49), Williams (Ralph, 79); Foley (Dawson, 74), Hayter
Subs not used: Reid, Stewart
Referee: Darren Sheldrake