Joe Jacobson struck home a late penalty for the Chairboys to earn a 2-2 draw at league leaders Portsmouth at Fratton Park.
Bryn Morris stroked home a sublime opening goal to put the Blues 1-0 up at the break, but Gareth Evans and Brett Pitman turned the game on its head following excellent assists from Jamal Lowe.
However, there was to be another twist in the tale when Christian Burgess fouled Fred Onyedinma in the box and Jacobson made no mistake from 12 yards, sending the visitors home with a point they fully deserved.
Gareth Ainsworth made three changes from the side that had started in the 0-0 draw with Oxford the previous week, handing a league debut to Darius Charles in defence while Adebayo Akinfenwa and Scott Kashket came into the attack with Anthony Stewart, Craig Mackail-Smith and Randell Williams missing out.
Wanderers started well on a difficult pitch which was spraying up water in some areas following a pre-match downfall, with the visitors taking a patient, passing approach in a bid to break down the league leaders.
Portsmouth threatened with a header from a free-kick which was well beaten away by Ryan Allsop, while at the other end, Adebayo Akinfenwa's looping header was claimed by the Craig MacGillivray before the keeper dropped a deep free-kick and Fred Onyedinma's shot from the loose ball was deflected behind.
For the most part, Wycombe were keeping the hosts quiet and the Fratton Park crowd were stunned into silence on 21 minutes when Bryn Morris curled home a beauty from 20 yards, playing a one-two with Adebayo Akinfenwa before giving the keeper no chance.
With his effort at Bradford eventually being taken away from him by the Dubious Goals Committee, there were no doubt that this one belonged to the Shrewsbury loanee, and his stylish knee slide across the wet turf was evidence of his delight at ending his drought.
Jamal Lowe drilled into the side netting, almost in anger as the hosts found themselves unable to threaten to the same extent that had seen them soar to the League 1 summit in the first eight games.
Jason McCarthy saw yellow for a foul on Ronan Curtis as the winger looked to step up the pace on the left-hand side, before Sido Jombati followed suit despite his vehement protests that Lowe had gone to ground with no contact.
From the resulting free-kick, Christian Burgess was unable to get enough power on his header to trouble Allsop, and then Onyedinma was bafflingly booked after the linesman alleged that he was the guilty party in a 50-50 battle.
There was a chance for Tom Naylor to level when he turned Lowe's cross goalwards on 43 minutes, but Allsop kept the ball out with his feet before collecting the loose ball first.
Then Kashket was the latest entry into the card-happy ref's notebook on the stroke of half-time, but the only contribution to his goals tally was that of Bryn Morris as he blew for the interval.
Jamal Lowe was the first Pompey player into the book after the break, tripping Bryn Morris, before Wycombe were close to doubling their lead when Matt Bloomfield's fine volley looked to be heading for the top corner, only for it to strike Kashket and fly over - with the striker being in an offside position anyway.
Portsmouth looked to be running out of ideas, and were preparing a double change, just as their equaliser came before the hour mark. A loose clearance fell to Oliver Hawkins who fed Lowe on the right side of the box, and although the striker was forced too wide of goal to shoot, he delivered an inch-perfect cross for Gareth Evans to head home from six yards out.
Game on, then, and Nathan Thompson saw yellow for stopping Onyedinma's breakway illegally, before Gareth Ainsworth swapped Scott Kashket with former Pompey youngster Paris Cowan-Hall, who had scored in the Chairboys' FA Cup win here two years ago.
The hosts were buoyed from their goal via a cross and looked to repeat the feat, getting the ball wide at all opportunities with Hawkins the target man in the box, requiring some well-timed blocks and clearances from the men in white.
But it was Wycombe's own focal point who could and possibly should have scored next, with Bryn Morris's delightful cross being flicked towards the back post by Akinfenwa, missing by inches.
Then action swung to the other end with a quick goal-kick and a one-on-one opportunity for Jamal Lowe, who was brilliantly denied by Allsop, who diverted the shot behind for a corner.
Portsmouth's change did come, and it was Hawkins who was withdrawn with Brett Pitman taking his place on 69 minutes.
Onyedinma caused problems again and forced Burgess into a bookable offence for obstruction, and then Morris saw a rocket blocked en route to goal after Jacobson's corner was half cleared.
Morris then went close again with a fierce free-kick which bent round the wall but didn't come back enough to nestle inside the post, before Pompey made their second change, bringing on Joe Mason for the goalscorer Evans.
Nathan Thompson went close with a well-hit curling effort with the outside of his right boot which flew narrowly wide, before Pompey completed the turnaround through super sub Pitman, who could barely miss the chance presented to him a yard out. Lowe dinked another sublime cross to the back post and Pitman no mistake.
But then came a lifeline. Wanderers kept the ball alive following Jacobson's deep free-kick and Christian Burgess recklessly shoved Onyedinma, giving the ref no option but to award the penalty. Jacobson stepped up and, with the demons of Luton on his shoulder, made no mistake, confidently finding the net to make it 2-2 with two minutes left on the clock.
There were five minutes added on, with Curtis Thompson being called from the bench to shore up the midfield in place of Bloomfield. Stoppage time was lengthened due to a head injury sustained by home defender Nathan Thompson, and it was gone 5pm by the time the final whistle sounded.
But when it did, it signalled the end of a mammoth effort from the Chairboys, who fully deserved their point which makes it one defeat in nine in all competitions.
Attendance: 18,648 (749 from Wyconbe)