It was a game United totally dominated from the kick-off, yet it took a superb save from Kenny Giles in the 85th minute to deny Darvel an undeserved point.
The United support were left wondering how on earth the scoreline remained at 1-0 when Stefan Law alone should have scored a hat-trick.
United went on the attack right from the kick-off and with just a minute played took the lead.
A ball played through from the midfield found Scott McManus on the left and he lobbed the ball in toward the back post where Paul McMenamin tapped it past the helpless keeper.
Three minutes later Cumbernauld should have extended their lead. A free-kick floated in by Conor Stevenson found the head of Paddy McCabe but his header was saved by the Darvel keeper.
Next up to test the goalie was Scott Davidson. Tony Stevenson found him with an excellent through ball, but somehow the keeper managed to get a hand to his strike which seem bound for the top corner.
It was all United and the Darvel defence must have been wondering just how they could stop this Cumbernauld team.
Even the United defenders were keen to have a go. Tony Stevenson gathered the ball in his own half and surged forward before launching a fierce shot that slid agonisingly past the post and into the side netting.
The ball was cleared off the line four times in a frantic five-minute spell around the half hour.
A header by Law from a Conor Stevenson corner was cleared off the line by the Darvel defence with the United fans appealing for the goal convinced the ball was over the line, then Davidson, McManus and McCabe were all denied when their efforts too were cleared away.
Darvel’s only effort on goal in the first half came on 37 minutes, but this was easily dealt with by Giles.
Five minutes into the second half Darvel were awarded a free-kick just outside the box after a mistimed tackle by Paddy McCabe, which resulted in the United player being shown the yellow card.
The well struck kick took a horrible bounce just in front of the goals, but Giles managed to gather it in at the second attempt.
Aiden Malone, on for the injured McManus, was next up to try his luck; he turned the Darvel defender but saw his shot come off the post.
The onslaught continued and Law, through on goal with only the keeper to beat, watched as his strike came off the post and was cleared away by the beleaguered defence.
With the minutes ticking away Darvel almost got a goal that would have sent the Nauld fans home in tears; an excellent move from then seen a strike fired in across the goal and but for a tremendous save from Giles would have given them an undeserved equaliser.