Full-time from The Den
The Chairboys, who grabbed a dramatic injury-time FA Cup winner in SE16 virtually a year ago to the day, broke the deadlock with a 50th-minute penalty from former Lion Adebayo Akinfenwa, only for David Worrall to level three minutes later with a low cross-shot that squirmed in at the near post.
Fred Onyedinma then spurned a glorious opportunity to edge The Lions ahead, but saw his 71st-minute penalty saved by Jamal Blackman. As the game headed towards a sudden death penalty shoot-out, Thompson took centre stage, lashing home an 84th-minute second before a close-range tap in on 90 minutes sealed victory for the League Two side.
Ben Thompson, who had scored his first senior goal in that FA Cup tie, went close to opening the account with a thumping 25-yarder that zipped narrowly off target, but then the half virtually developed into a personal battle between Onyedinma and the Wycombe rearguard, who thwarted his every attempt to get on the score-sheet.
Thompson did well to slip the ball through to Millwall's No.10 on 26 minutes only for a defender to block the striker's goal-bound shot. Onyedinma was nearly played in again, this time by Jimmy Abdou, only for former Lions youngster Will De Havilland to step in and intercept.
Onyedinma was clean through on goal 10 minutes before the break, but the goalkeeper’s presence proved too much for the Lions' attacker and his heavy touch went out for a goal kick.
Wycombe introduced the man-mountain that is Akinfenwa at the start of the second-half, and the powerfully built striker certainly made a big impact.
Within five minutes of his introduction Akinfenwa was sweeping home the opening goal with a calmly converted spot-kick after Sid Nelson had been penalised for a foul on Stephen McGinn.
However The Chairboys' celebrations were short-lived and just three minutes later Worrall broke down the right, looked up and whipped in an angled cross-cum-shot that caught Blackman unawares and the ball squeezed into the back of the net between the keeper and his near post.
Onyedinma was involved again just seconds later, flicking the ball into the path of Twardek, whose close range shot was blocked for a corner as The Lions began to build up a head of steam.
A flurry of strong challenges on the lively Onyedinma went unsighted by the officials until the 71st-minute when the frontman was sent sprawling after he weaved his way into the penalty area following a neat interchange with sub Harry Smith.
Holding onto the ball despite the plea of sub Smith to take the resulting spot-kick, Onyedinma stepped up but was yet again thwarted by the visitors, with Blackman throwing himself low to his left to push away the penalty at full stretch.
Twardek went close to grabbing an equaliser in the 89th-minute minute only to see his firm header drop inches off target.
Scorer: Worrall (53mins)
Wycombe Wanderers: Blackman, Jombati, McGinn (Kashket, 74mins), Thompson, Bean, Hayes (Akinfenwa, 46mins), Wood, Harriman, Rowe, Muller (Pierre, 58mins), De Havilland. Subs not used: Richardson, Jacobson.
Booking: De Havilland (82mins)
Scorers: Akinfenwa (50mins, pen), Thompson (84, 90mins)
Ref: D Whitestone
Att: 1,619 (away 88)
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