Down seconds travelled to Lisburn with just 10 men for this Junior 6 tie and Mark Graham's side played well in parts, but was always going to be up against it.
The locals once again had a lot of young players in their line-up with the game played on the shale which was a boost for the visitors who had to rely on a few old heads when the going got tough. Cecil Telford did what he could, but the one-man advantage made a huge difference.
The opening 10 minutes were pretty even but South Antrim's persistence was rewarded in the 12th minute when they took the lead from play with a forward given too much time to pick his spot past David Moreland.
South Antrim made it 2-0 in the 20th minute with another goal from play and three minutes later they led 3-0 when Moreland was again left without defensive cover.
Skipper Graham gave the visitors a glimmer of hope two minutes later when he fired home a short corner strike which had been won by the impressive Jordan Wade.
Just before the interval Graham "scored" again via deflected shot, but the home umpired disallowed the goal, much to the consternation of the visitors.
Down started well at the start of the second period and Graham teed up Lewis McIntosh who couldn't get a touch on the ball to deflect it home and then a great run by Wade, who side-stepped three South Antrim defenders, saw him pick out Andy Teggart.
In acres of space and with more time than he realised, Teggart rushed his shot and the opportunity was lost. Within nine minutes, South Antrim scored to take a 4-1 lead and midway through the half it was 5-1.
With 10 minutes t go and Down legs tiring, the home side made it 6-1. But Down don't have to wait long to exact revenge as the sides meet this weekend again on the shale, but this time at Malone Park.