Bob Dowie made eight changes to his starting line-up, gave defensive debuts to Andy Alexander (ex Grays), Mark Rooney (Watford), and Kenny Webster (Stevenage/Harrow Borough) and named himself as a substitute.
In normal time, the closest United came to scoring was on 43 minutes when skipper Richard Harvey shot through a crowded area, past keeper Wells but Silk got back to clear off the line.
In extra time it was difficult keeping up with matters. On 103 minutes Cove looked well offside but with no flag he advanced and rounded Richard Wilmot to score.
On 107 minutes Nelson was brought down from behind by Dowie for a penalty. Dowie got a red card and Read made it 2-0 from the spot.
On 109 minutes Cove outran Alexander to chip over Wilmot from outside the box, then four minutes later Nelson went down in the box for another penalty and Webster was sent off. Wilmot saved Cove's penalty.
After 117 minutes Cove made amends by heading in a cross for 4-0, then on 119 minutes (a minute from the end) sub Gary Crawshaw turned to chip over Wells to score nothing more than a consolation for a 'depleted' United team.
Aylesbury United
Leyton Pennant
Abingdon Town
Slough Town
Barton Rovers
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Boreham Wood
Enfield
Bromley
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Dulwich Hamlet
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Harrow Borough
East Thurrock United
Hemel Hempstead Town
Romford
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Leatherhead
Corinthian Casuals
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Uxbridge
Maidenhead United
Lewes
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Yeading
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Whyteleafe
Gravesend & Northfleet
Windsor & Eton
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Worthing
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