Erith Town crashed out of the Kent Reliance Senior Trophy quarter-final despite a gutsy display against Whitstable Town.
The Dockers went behind on 10 minutes when Dan Palfrey was ruled to have brought down Ricky Freeman. who duly converted from the spot.
Harrison Hume, booked for protesting the penalty, then got his marching orders for a second bookable offence.
With goalkeeper Adam Molloy in fine form, Erith continued to put Whitstable under pressure.
But all their good work was undone by a reckless challenge by defender Jack Hooper which saw him handed a second yellow card.
Nine-man Erith were finally undone on 75 minutes when Gillman stabbed home the second.
The Dockers are in action this Wednesday when they host Crowborough Athletic in the SCEFL Challenge Cup (7.45pm) and also Lordswood on Saturday in the SCEFL Premier Division (3pm).
Bridon Ropes won 2-1 against Lydd Town in the SCEFL First Division. Erith & Belvedere drew 3-3 at home to Graveshame Borough.