Wolves 2 (Milijaš-pen 26, Stearman 120+3)
Southend United 1 (Easton 80)
Just seconds before the end of added time in extra-time, skipper for the night Richard Stearman netted the winner against a brave and unlucky Southend United team.
Moments before Stearman's last gasp effort, it was The Shrimpers that almost progressed to the third round of the Carling Cup but midfielder Josh Simpson spurned a great chance when he shot straight at Wayne Hennessey.
There were ten changes to the team that started against Everton with Danny Batth and Sam Winnall both making their senior debuts. There was also an outing for another of the club's young professionals - Ashley Hemmings.
In the opening minutes Glenn Morris in the Southend goal had to punch clear a long throw from Greg Halford and at the other end George Elokobi headed out a corner from Sofiene Zaaboub.
Southend were awarded a free-kick after Adlene Guediuora's challenge on Anthony Grant who fired over the angle from 30-yards when the kick was played to him.
A Nenad Milijaš free-kick was half cleared to Batth whose overhead kick from the edge of the box went straight into the arms of Morris.
Another free-kick, this time taken by Zaaboub, was laid into the path of Grant whose low shot hit a defender and flew behind for a corner.
Wolves took the lead in the 27th minute after Winnall was tripped in the box by Chris Barker. Milijaš made no mistake from the spot blasting the penalty past Morris (pictured).
Southend should have been level four minutes later but Bilel Mohsni headed narrowly wide of the far post from close in after Peter Gilbert had lifted a free-kick into the home area.
Mohsni did have the ball in Hennessey's net in the 35th minute but the flag had been raised for offside.
There was a moment of danger for Wolves when Grant ran from just inside the Wolves half and cut inside before hitting a low drive that was well taken by Hennessey.
There was a brief skirmish after Winnall slid on the keeper who had just clung onto a Dave Edwards header following a Milijaš corner then, just before the half drifted into stoppage time, Simpson burst through the middle and lifted a shot narrowly over the bar.
Half-Time: Wolves 1 Southend 0
A neat piece of ball control saw Barry Corr carving out a shooting opportunity for himself but Hennessey had positioned himself perfectly to cut out the drive that followed.
Winnall was shown the yellow card for persistent fouling after he had controlled the ball with his hand before Morris dived to hold on to a low effort from Hemmings.
Only a last ditch tackle from Mohsni prevented an almost certain goal from Guedioura and, on the hour mark, Winnall nearly capped his debut with a stunning goal but his volley just beat the far post after Hemmings had supplied the cross from the right.
Ronald Zubar won the ball in midfield and beat two men on a run to the edge of the Southend box but Morris got behind the French defender's low shot.
Blair Sturrock clipped the top of the bar with the referee ruling that Hennessy had got a touch on the ball and awarding a corner.
With 20 minutes remaining both teams made a double switch with Winnall and Hemmings getting a warm reception from the crowd as they left the field to be replaced by Kevin Doyle and Sylvan Ebanks-Blake.
Gilbert then went into the book for a late tackle on Zubar who needed treatment before he was able to resume.
With ten minutes remaining Southend equalised through Craig Easton's diving header after a well delivered cross from Sean Clohessy.
Two minutes later Ebanks-Blake prodded home a low cross from Zubar but he was deemed to be offside.
90 Minutes: Wolves 1 Southend 1
Kevin Foley replaced Edwards at the start of extra-time which was just 20 seconds old when Halford had two attempts at goal with the first being blocked by a defender and the second ending in the arms of Morris.
Easton was yellow carded for pulling back Doyle and then Ebanks-Blake had another 'goal' ruled out for offside after a Milijaš shot was deflected onto the inside of a post by a defender.
Batth scooped the ball over the bar after a Milijaš corner and, after the change round, another great tackle from Mohsni denied Doyle who would otherwise have been clean through.
With the game entering it's final moments, Simpson looked on to get the winner as he charged in on substitute Louie Soares's centre but his first time shot whet straight into the midriff of Hennessey.
Then came the last gasp winner as Zubar cut into the United box and drove the ball deep into the six-yard box where it hit a defender before Stearman guided it over the line from a yard out to break Essex hearts.
Wolves: Hennessey, Zubar, Elokobi, Edwards (Foley 90), Stearman (capt), Batth, Halford, Milijaš, Guedioura, Winnall (Doyle 71), Hemmings (Ebanks-Blake 71).
Unused subs: Berra, Ikeme, Davis, Malone.
Bookings: Guedioura (30 - foul), Winnall (50 - persistent fouling).
Southend: Morris, Clohessy, Gilbert, Simpson, Mohsni, Grant, Easton (capt), Corr (Soares 71), Zaaboub (Hall 71), Sturrock (Paterson 78), Barker.
Unused subs: Bouzid, Prosser, Evans, Spencer.
Bookings: Gilbert (73 - foul), Easton (92 - foul).
Referee: C.H. Webster.