Holwell Sports were sunk by a last-gasp goal after a rusty display as they returned to action for the first time in three weeks.
The hosts looked comfortable for most of the first half, but Arnold grew in stature and were good value for their very late winner.
Holwell were led by assistant Ryan Peacock as John Webster began a four-match FA ban, and they looked lively enough at the start.
Cropper, in for the unavailable Chapman, sent in a telling cross which Arnold’s keeper Reece Jackson let slip through his hands, but no home forward could capitalise.
And a minute later Mark Tinsley controlled a long ball out of defence and, spotting keeper Jackson off his line, lobbed him from 35 yards to put the home side in front.
Holwell’s long absence from competitive action was telling with poor passing and a lethargy in their approach in a scrappy first half.
Chris Hibbitt had the ball in the net after 15 minutes when he rose well between the keeper and defender, but referee Scriven ruled the midfielder had fouled the keeper and disallowed it.
Arnold’s front pair of Joe Butler and Barry Payne gave the home defence plenty to think about. And Payne had a big penalty shout when his downward header bounced up and caught Aaron Ridout’s outstretched arms as he fell backwards, but referee Scriven waved away the appeals.
Holwell struggled to break down the visitors’ defence, but were in control and almost doubled their lead after 25 minutes.
Hazeldine won the ball on the left and found Tinsley with a good pass, but Reece did very well to save low down at the right-hand post.
Arnold went close a minute later when Price’s ball into the box found Payne’s head, but Witham got down well to his left-hand post to parry, and Fatta’s shot on the rebound was straight at the keeper.
Arnold grew stronger as the half wore on and were rewarded on 38 minutes when the dependable Rob Woodcock misjudged an incoming cross which hit him on the arm. A clear penalty which captain Luke Smith dispatched.
The visitors finished the half on top, but it was Holwell who nearly went into the break ahead when Michael Stevenson’s shot forced a sharp save from Jackson, low to his right-hand post.
The second half was a dour affair with scrappy play from the hosts as Arnold looked the more dangerous throughout.
Butler and Payne tried hard to break down a resolute home defence as Bitmead and Woodcock again did well to keep Holwell in the game.
Things got heated in the 70th minute when Bitmead fouled Fatta on the edge of the penalty area, and Michael Pearson was perhaps lucky not to be sent off as he tried to get involved with Hibbitt.
The officials took several minutes to calm the players with bookings for Holwell’s Bitmead and Hibbitt, and Arnold’s Fatta and Pearson. This delay would come back to bite Holwell.
As the game drew to a close the hosts looked just about on top, but Arnold used the additional few minutes to their advantage.
Charles missed a great chance when he headed over before Payne crowned a solid performance with a thunderous shot into the top corner in the second minute of stoppage-time.
Holwell: Witham, Ridout, Bitmead, Woodcock, Cropper (Harris), Foster, Hibbitt, Stevenson, Wells, Hazeldine (S. Smith), Tinsley. Sub not used B. Smith.