Sevenoaks Town’s record breaking FA Vase run is over following this third round exit.
Hopes of a place in the last 32 of the competition for the first time, faded in misty, murky Berkshire, as they conceded twice in the space of three first half minutes.
Club chairman Paul Lansdale watched the game - his first since undergoing major surgery last month.
Boss Micky Collins thanked the club’s support, admitting Sevenoaks were beaten by the better side on the day, maintaining winning the league was now priority.
Home top scorer Shane Cooper-Clark scored both - putting Thatcham in front after 36 minutes, before making it 2-0 from the penalty spot after Harrison Carnegie was harshly adjudged to have handled the ball on the edge of the box.
London referee Andreas Anastasiou had already pointed to the spot earlier after Town skipper Corey Holder felled Ekow Elliott - only to change his mind after Sevenoaks protests claimed the foul was outside the box leading him to consult his assistant.
Carnegie pulled one back just before the hour, only for Town to concede six minutes later when Elliott was left with a simple tap-in after visiting keeper Ben Bridle-Card failed to hold Harry Grant’s cross.
To make matters worse for Town they lost Rory Hill with a knee injury in the second half.
Bridle-Card did well to push away Cooper-Clark for a corner after only three minutes. Latest signing Frankie Sawyer then missed a great chance to put his side in front on his debut, flicking the ball over the bar from Chris Edwards’ cross from the right.
Carnegie looked to have won a penalty as he went down in the box, but Mr Anastasiou wasn’t interested on that occasion.
The winger then fired over the bar, before Thatcham took control with two rapid strikes - Carnegie very unlucky after the ball was blasted at him from close range.
It gave Thatcham the edge at half-time, but Carnegie gave Town hope with an angled finish.
The home side’s third meant they were short-lived and Hill’s injury was another blow.
Sevenoaks sub Byron Walker went close with one instinctive effort just over the bar, and saw another headed off the line late on.
Town return to league action on Saturday with a trip to bottom side Hollands & Blair (KO 15:00) and they entertain Lordswood on Tuesday 12th December (19:45) in their first home game for more than six weeks.