Potton latched onto a loose ball in the area after Hemel's goalkeeper Jamie Butler had his effort blocked on the line deep into second half stoppage time, snatching a point from the jaws of defeat for the home side.
Chelmsford were made to rue missed chances in the second half having taken the lead midway through the first half after Adam Bailey-Dennis turned Jack Bridge's cross into his own net.
City's best chances in the second half fell to striker Billy Bricknell and on another day the Clarets could have been out of sight. But instead City were forced to accept one point rather than three after Potton's late equaliser.
Having won so impressively against Maidenhead United at home on Saturday it came as no surprise to find out that Kevin Maher had named an unchanged line-up to start the match against Hemel, who were in search of a fourth straight win.
The opening 20 minutes went by with very little being created by either side, but that was until Christian Dibble was forced into tipping Nikolay Todorov’s header around the post midway through the half.
Dibble was then called into action again a few minutes later when a short corner resulted in Graeme Montgomery finding space for a shot which took a deflection off Rob Girdlestone before being gathered comfortably by City’s on-loan goalkeeper.
Despite Hemel having the best of the very few goalmouth chances it was the away side that would break the deadlock with their first effort on goal thanks to a helping hand, or chest, from Adam Bailey-Dennis.
A quick punt up field from Dibble was misjudged by Hemel captain, Ben Herd, and allowed Jack Bridge to attack the Hemel back line. After beating Harry Hickford, Bridge crossed the ball into the danger area and watched as the ball cannoned off the chest of Bailey-Dennis and into the back of the net.
Since returning to club on loan from Southend United, Bridge has been nothing short of a revelation, and having before involved in setting up Chelmsford’s opener he was involved again, linking up well with Bagasan Graham to create a chance for Sandro Semedo which was saved by the legs of Jamie Butler.
Hemel’s best chance of the half fell right on the stroke of half time after a cross-field ball found its way out to Montgomery on the left wing. After cutting inside to create space for the shot in the area the striker’s initial effort beat Dibble but was blocked by Mark Haines, with the Clarets centre half recovering well to then clear the ball off the line whilst under pressure from Ibra Seklajja.
Against Maidenhead United on Saturday the Clarets took a while to get their act together when they returned for the second half, but there was no such problem against Hemel.
If anything the visitors will feel that they should have doubled their lead when Billy Bricknell beat the offside trap to be one-on-one with Butler, but the City striker failed to lift the ball over the on-rushing goalkeeper and extend Chelmsford’s advantage.
Bricknell again had an opportunity to put City 2-0 up and effectively kill off the match when Hemel sloppily lost the ball in midfield. Graham’s first time pass found Reece Prestedge who laid the ball off for Bricknell, but the striker failed to get the ball past Hickford who’d recovered to deflect Bricknell’s effort over the bar.
The home side would go about trying to make City pay for those missed chances in front of goal, but they found it difficult to get through a sturdy Clarets defence.
Montgomery came close when he connected with a low corner only for his effort to be deflected narrowly wide of Dibble’s near post, before in injury time the Hemel number 11 tried his luck from range forcing Dibble into a routine save.
It looked like City were destined for all three points as four additional minutes were shown, but as the clock ticked into the final minute of those four the home side forced one final assault on goal after Harry Morgan fouled Herd wide on the left.
Having scored a spectacular equaliser against Sutton United a few weeks before, goalkeeper Butler went up to cause City more defensive problems and he almost scored again when Dibble’s punch fell to his counterpart. Butler’s toe-poke was blocked but the rebound fell kindly for James Potton to prod in the equaliser from two yards out to snatch an unlikely point for the home side.
There was just about enough time for City to take the kick-off before referee Ian Rathbone called time, leaving both teams having to settle for a point when it looked like all three were going back to Essex.
The draw meant that the Clarets remain in 15th place in the table, but with Whitehawk, Bath City and Weston-super-Mare – all teams below City – all losing the Clarets now have a six point cushion between themselves and the bottom three.
That cushion could well have been eight points had Chelmsford held on for the win, but after the match Clarets Caretaker Manager, Kevin Maher said “that’s the only downside to the evening that we haven’t picked up maximum points. Apart from that I thought the players were brilliant.”
“To come here on a cold, wet Tuesday night and perform like they did, and stand up to what they had to deal with was brilliant.
“The way we performed and hit them on the break was top class, but we just were lacking that little bit of quality in the final third by not taking our chances and we could have been out of sight before the end.”
Hemel Hempstead Town
1. Jamie Butler
2. Ben Herd (C)
3. Jack Kelly
4. Adam Bailey-Dennis
5. Harry Hickford
6. Ibra Seklajja
7. Ricky Wellard
8. Michael Richens
9. Nikolay Todorov
10. James Potton
11. Graeme Montgomery
12. Gary Connolly
14. Matthew Saunders (On for Nikolay Todorov 57’)
15. Dean Brennan
16. Luke Jones
17. Matthew Spring (On for Jack Kelly 46’)
1. Christian Dibble
2. Rob Girdlestone
3. Marvel Ekpiteta
4. Reece Prestedge
5. Mark Haines
6. Rory McAuley (c)
7. Harry Morgan
8. Jack Bridge
9. Billy Bricknell
10. Sandro Semedo
11. Bagasan Graham
12. Luke Daley
14. Timothy Monsheju
15. Marvin Ekpiteta
16. Lee Sawyer
17. Connor Pearce
Hemel Hempstead Town: James Potton 90+4’
Chelmsford City: Adam Bailey-Dennis O.G. 32’
Hemel Hempstead Town: Michael Richens Booked (Foul – 72’), Harry Hickford Booked (Obstruction – 74’)
Chelmsford City: Mark Haines Booked (Dissent – 62’)
Referee: Ian Rathbone
Assistants: Andrew Humphries & Mark Wardell
Clarets Man of the Match: Mark Haines