Korsten curled home a delightful free-kick from the edge of the area with 16 minutes of the FA Premier Reserve League encounter remaining.
That should have made it 1-1 but referee Mr Bassindale called play back to penalise Derby’s Dean Sturridge and order a retake. Sturridge was booked — although the 10-yard penalty was not brought into play — and, naturally, the retake was charged down.
Derby went on to win 3-0 at a rain-soaked Pride Park with Deon Burton scoring two late goals including an injury time penalty to claim a hat-trick.
Reserve boss Hughton said afterwards: "When I spoke to the referee — and I’ll have to check this one — he said we don’t play the 10-yard rule at this level.
"That being the case I then asked why he disallowed the goal. He said that he had blown the whistle before the ball had gone in the back of the net. That was very, very poor, I’ve got to say. That’s not an excuse for our performance though because we simply didn’t perform very well."
The final scoreline was still somewhat harsh on Spurs who had at least as much possession as the home side and, despite Burton’s treble, had actually handled the potentially dangerous strikeforce of Burton and Sturridge well.
Hughton added: "If I’m looking in all honesty, Matthew Etherington had a couple of terrific runs down the left, getting the ball in the box and young John Jackson applied himself well at left-back but apart from that there isn’t anyone else I could pick out and say that he played well.
"Certainly though up to the time they scored their goal they didn’t really create much."
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Chris Hughton was left bemused as to why Willem Korsten’s ‘goal’ for the reserves against Derby County was chalked off on Tuesday night.