A stoppage time winner gave Wanderers all three points after an outstanding performance to come from behind at Birmingham City.
The Chairboys would have felt disappointed to trail at the break to Marc Roberts' header, but their second half dominance paid off when Scott Kashket turned home Fred Onyedinma's shot before Onyedinma played a big part in the winner as he helped steer the ball over the line following a corner.
Richard Dobson – leading the side again with manager Gareth Ainsworth recovering at home from a back operation – named an unchanged squad from the one that collected its first victory of the season at the weekend, pairing Adebayo Akinfenwa and Scott Kashket in attack again with David Wheeler and Daryl Horgan supporting from out wide.
At the other end, Dennis Adeniran made an important block as space opened up for Ivan Sanchez to get a shot away from just inside the area, and then Ryan Allsop tipped over Harlee Dean’s powerful drive from the edge.
Jacobson threatened again from a corner, nearly scoring directly from a delivery which narrowly evaded the far post, before City’s own left-sided dangerman Jeremie Bela curled a delicate cross-shot just wide.
Wycombe’s number 3 went close again but this time with a classy run and piece of skill to beat two defenders before drilling narrowly wide from the edge of the area, and was denied a stunning opener on 38 minutes when his sublime free-kick was tipped away from the top corner by Neil Etheridge in goal.
But within moments, the visitors were behind. A corner from the right landed dangerously into a cluster of players and it was Marc Roberts who forced it home with a fierce header, giving Allsop no chance.
The keeper was called upon to prevent a second goal soon after when he kept out Lucas Jutkiewicz’s bullet header as the hosts cranked up the pressure, but their lead remained a slender one-goal advantage going into half-time.
Jutkiewicz stung the palms of Allsop with the first chance of the second half, seizing on Bela’s pass, before an excellent, patient build-up almost brought the Chairboys level but Akinfenwa couldn’t quite convert Horgan’s low cross under pressure from the defender.
Wycombe brought Anis Mehmeti and Fred Onyedinma off the bench on 63 minutes as Dennis Adeniran and David Wheeler made way, and the changes gave the side more impetus as Birmingham opted to sit back and attempt to soak up pressure to see out the 1-0 win.
It didn’t work. Onyedinma was the catalyst for the equaliser, finding space at the end of a patient move to get his shot away, and the ball cannoned off Kashket and into the net to bring Wanderers deservedly level.
They then almost took the lead when Onyedinma lashed the ball across the face of goal and Horgan was inches away from meeting it, with Wycombe continuing to hold the upper hand and play at the greater tempo at the clock ticked towards 90.
Daryl Horgan won the corner that led to the winner in stoppage time, with his rocket of a shot taking a deflection and going behind, and from Jacobson’s corner, Neil Etheridge’s unconvincing punch was returned to danger by Josh Knight and bundled home by a combination of Onyedinma and Blues defender Kristian Pedersen as the celebrations rang out from the away bench… and the Ainsworth household over 100 miles away.