Tjay De Barr was the hero on a dramatic debut for Wycombe, who moved into the third round of the Carabao Cup following a 5-3 win on penalties against Stevenage.
The Gibraltar international first rescued the Chairboys with a late, late equaliser to make it 2-2 before he sealed their progress with a nerveless spot-kick in the shoot-out.
Wycombe were ahead after 24 minutes when Joe Jacobson's shot ricocheted into Adebayo Akinfenwa's path and the veteran striker made no mistake in blasting his shot home.
Stevenage drew level six minutes into the second half when captain Luke Prosser hooked the ball towards goal and Elliott List was on hand to tap in from almost on the line.
Boro took control and went ahead with 13 minutes left when Luke Norris fed the ball into Jamie Reid's path and he steered his shot into the bottom corner.
Wycombe were not finished, though, and equalised in the fourth minute of stoppage time when De Barr was able to head in a terrific cross by fellow substitute Daryl Horgan.
This forced a shoot-out and after Stevenage's Luther James-Wildin blazed over from 12 yards, De Barr made himself the hero again, sending Joseph Anang the wrong way.