A late strike from Craig Easton snatched the points for Southend United in a topsy-turvy battle at Roots Hall on Tuesday evening.
Jon-Paul Pittman opened the scoring before half-time with a tidy finish for his first strike since returning from injury, but the hosts turned the game on its head after the break with two goals in quick succession.
Headers from Barry Corr and Kane Ferdinand made it 2-1 before Nikki Bull saved a weak penalty from Blair Sturrock, and the Blues looked to salvaged a draw when Scott Rendell netted a spot-kick of his own on 88 minutes.
However, Easton's late strike settled the match and condemned the visitors to back-to-back defeats ahead of successive home matches in the next seven days.
Gary Waddock rung the changes for the clash in Essex, recalling Alan Bennett, Scott Donnelly, Jon-Paul Pittman and Scott Rendell to the starting line-up at the expense of the injured Chris Westwood, Gareth Ainsworth, Kevin Betsy and Ben Strevens.
Wanderers, in their new 4-3-3 formation, settled quickly and threatened early on through stand-in captain Matt Bloomfield and Pittman, while, at the other end, the hosts were looking to use the outlet of pacey Ryan Hall down their right.
Despite some good football being played by both sides in the opening exchanges, the first chance didn't come about until the 13th minute when Bloomfield fired a shot over the top after a typical surge forward from Wycombe's No. 10.
Paul Sturrock's men responded well and were unlucky not to take the lead five minutes later when former Wanderer Anthony Grant hit the base of the right post from close range after a teasing cross from Hall had caused mayhem in Wycombe's box.
That seemed to kick-start the Chairboys once again, with Scott Donnelly arrowing a scorching 25-yard effort just over the top before Bloomfield drove wide after latching onto Scott Rendell's neat through ball.
Gary Waddock was forced into a change on 28 minutes when Kevin Betsy replaced the injured Matt Bloomfield, and Betsy nearly made an immediate impact with a blistering effort which narrowly missed the target.
The breakthrough came just two minutes later, though, when a crisp passing move involving Marvin McCoy, Scott Rendell and Stuart Beavon set-up Pittman, who gave Evans no chance from 15 yards. The goal itself - JP's first since the opening day of the season - was a joy to watch but the celebration was not quite so polished, with all ten outfield players indulging in a bizarre dance routine.
The goal failed to sting the hosts into life and the half ended with neither side creating much in front of goal, with the Wanderers looking comfortable with their lead.
But how things changed within just 15 minutes of the restart. After the Blues had looked so comfortable with balls into the box throughout the first half, it was a routine header from a corner which levelled the scores as Barry Corr converted Ryan Hall's centre. Corr was unmarked and it was a poor act of defending from the visitors, which gave Southend the momentum.
And they used it well, taking the lead on the hour-mark when another cross was headed home by Kane Ferdinand from an unmarked position.
Wycombe were stunned, but reacted positively and after being unable to convert following Rhys Evans' slip near the corner flag, Stuart Beavon hit the crossbar when the keeper dropped the ball in his path.
Scott Donnelly then saw his free-kick fly just wide before Grant won a penalty when Marvin McCoy got the wrong side of the midfielder and made contact, with the referee pointing to the spot.
However, a shocking effort from Blair Sturrock was easily kept out by the legs of Nikki Bull, giving Wycombe hope of capitalising on their newfound momentum. They had a couple of half chances instantaneously, firstly when Scott Donnelly's shot was deflected wide before a dangerous corner was close to being bundled over the line.
Hope appeared to have come when Peter Gilbert handled Gareth Ainsworth's cross and Scott Rendell netted from the spot with just two minutes remaining, but Wycombe switched off yet again to allow Craig Easton to crash home from the edge of the box as the game ticked towards stoppage time.
13mins: CHANCE - After bursting forward from midfield, Matt Bloomfield blazes a shot over Southend's bar from 25 yards.
14mins: CHANCE - Kane Ferdinand side-foots an effort just over Nikki Bull's bar from the edge of Wycombe's 18-yard box.
19mins: CHANCE - Former Wanderer hits the post from close-range after a teasing cross had caused mayhem in the Blues' box.
21mins: CHANCE - Donnelly arrows a stunning strike just inches over Rhys Evans' goal.
24mins: CHANCE - After latching onto Scott Rendell's through ball, Bloomfield shoots wide from 15 yards.
27mins: SAVE - Evans comfortably gathers Jon-Paul Pittman's tame effort.
28mins: SUB - Matt Bloomfield is replaced by Kevin Betsy.
29mins: CHANCE - Betsy almost makes an immediate impact with a fierce drive from 25 yards.
30mins: GOAL - After a fine attacking move involving Marvin McCoy and Scott Rendell, Pittman lashes home from 15 yards.
37mins:SAVE -Dave Winfield can't quite get enough on Donnelly's teasing cross to turn the ball past Evans.
45mins: BOOKING - Dave Winfield picks up his 11th yellow card of the season for a foul on Mark Phillips.
49mins: BOOKING - Pittman sees yellow for a foul on Anthony Grant.
50mins: GOAL - Barry Corr levels matters with a header from eight yards, completely unmarked.
60mins: GOAL - Kane Ferdinand heads home from the penalty spot after a cross from the right.
64mins: CHANCE - Stuart Beavon hits the bar after Rhys Evans drops a cross in his path.
69mins: SUB - Gareth Ainsworth comes on for Beavon as the Blues switch to 4-4-2.
69mins: CHANCE - Scott Donnelly's free-kick goes just wide.
70mins: SUB - Harry Crawford comes on for Barry Corr.
72mins: PENALTY - Marvin McCoy bundles over Anthony Grant.
73mins: SAVE - Nikki Bull keeps out Blair Sturrock's weak effort.
77mins: CHANCE - Scott Donnelly's free-kick flashes just wide.
88mins: PENALTY - Peter Gilbert handles in the box.
88mins: GOAL - Scott Rendell converts from 12 yards.
90mins: GOAL - Craig Easton fires the winner from the edge of the box.