Potton started as they have in recent weeks, giving their opponents little time on the ball, and on 12 minutes Jim Burnside forced an error from Arlesey goalkeeper Robbie Ponting as he was adjudged to have handled outside the box.
Jonny Hall’s free kick was blocked but played into the box to skipper Christian Smail who drove home from 12 yards.
United could have doubled their lead two minutes later when Danny Webb crossed but Burnside’s header was just over.
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Midway through the half Arlesey’s experienced Ash Fuller won the ball, turned and beat his man before hitting a good shot that brought a good save out of Tyler Josephs.
The Royals had two good chances to double their lead before the break. Burnside played a sublime ball to Webb who beat his man but they seemed to get caught in two minds as he tried to play the ball back to Burnside who did not have the space to get a shot on target.
Just before half time Smail played in Murrell but his shot was well over.
Potton came out in the second half with steel and determination and could have scored on 49 minutes when another link up between Webb and Burnside saw the powerful striker beat his man but his shot was just over.
Ten minutes in the ball was played over the top to Webb who sped away, drew the keeper out and placed his shot with perfection into the far corner to double the hosts’ lead.
Two minutes later and Potton were in dreamland when Arlesey did not clear a corner and the ball was played back in for James Sage to drive home for his first goal of the season.
Arlesey committed plenty of men forward and had their best spell of the match. A crossfield ball found Aaron Browne but his shot was wide while Darvall had a long range shot that the keeper spilled but nobody was near enough to collect.
Town’s Gaffney tried an effort from the wing that looked to have beaten Josephs but the ball was well cleared off the line. Fuller worked into the box and went down in a tangle with the defender but only a goal kick was awarded.
The best goal of the game was scored late on by sub Martin Danobrega. It was similar to his goal at Cockfosters where he beat three men on the edge of the box to drill the ball home from 18 yards which sped off the wet playing surface.
The Royals travel to Harpenden in the SSML on Saturday while Arlesey host London Colney.