Chris Lewington was the hero as Whites edged past Sittingbourne on penalties to advance onto the next round of the Kent Reliance Senior cup.
Dover’s keeper saved spot kicks from Tom Loynes and Mobalasi Dawodu as 10-man Athletic, the defending champions, won the shootout 4-1 after the second round tie ended 2-2 draw in normal time.
Chris Kinnear’s side also finished the game a man light after Aziz Deen-Conteh was shown a second yellow card in injury time.
Whites started brightly with Kane Richards cutting inside and firing straight at visiting keeper Harry Brooks early on.
But his effort was merely a warning shot and the winger opened the scoring on 22 minutes.
Jamie Allen collected the ball out wide and passed inside for Tobi Sho-Silva to tuck the ball into the bottom corner, via a slight deflection of Richards.
Debutant Lewington was called into action on the half-hour mark for the home side, beating away Ade Batula’s fierce drive, then denying Chris Webber with an identical block when the ball rebounded to the defender.
The home stopper then spectacularly tipped over Tom Loynes curling effort after the winger cut inside Chris Barnard.
David Smith fired narrowly wide from an angle for the visitors and Brooks palmed Oliver Muldoon’s volley around the post after Deen-Conteh’s run and cross.
But Sittingbourne were deservedly level eight minutes after the break. Webber’s set piece found Dawodu free in the box to head home.
Brooks had to be alert to deny Deen-Conteh at his near post and George Essuman nodded the resulting corner over the bar.
Sho-Silva headed Richards’ cross at Brooks and the visiting keeper was off his line quickly to beat Barnard to a loose ball soon after.
Smith fired wide once again as did Essuman at the other end, striking the side netting after Brooks’ punch from Deen-Conteh’s initial shot fell for the centre back.
The Brickies goalie also showed good agility to tip over Allen’s powerful drive from an angle.
The turnaround was complete on 78 minutes, sub Kane Rowland capitalised on Essuman’s error and fired home via the post.
But the the visitors could only hold on to their lead for four minutes as Deen-Conteh curled a free-kick into the top corner, before his evening turned sour after the referee gave the defender his marching orders following a rash challenge.
But the 10-men held firm until the final whistle, winning the shootout thanks to Lewington’s heroics.
Earlier, Kinnear made 11 changes to the side that started the 4-0 home win over Chester last weekend.
Whites are back in league action this Saturday when they travel to Guiseley. Kick off 3pm.
Dover: Lewington, Fazakerley(c), Deen-Conteh, Essuman, Adebowale, Barnard, Allen, Muldoon, Sho-Silva, Thomas, Richards.
Subs not used: Smith, Wratten, Dixon, Cusson, Hook.
Sittingbourne: Brooks, Webber, Elliott, Coker, Allan, Dawodu, Guthrie, Batula(Blake 73), Smith (Rowland 69), Cornwell(c) (Phillip 45), Loynes.
Subs not used: Brown, Hawkes.