The win marked their first in the UK since their introduction to the competition, their first victory this season and their first win against Ospreys.
The Port Elizabeth side made good use of their point-scoring chances in the first half with Scott van Breda (fullback) slotting over two penalty goals and converting a fantastic try by Erich Cronje, while their tenacious defence saw them shut out the hosts completely for a 13-0 halftime lead.
The second half was tense as the Isuzu Southern Kings managed to add only an early penalty goal to their score, while Ospreys fought back with intent, scoring back-to-back tries to trail by two points with minutes to play, before being awarded two kickable penalty goals, which would have sealed the win for them. But their attempts at the posts were unsuccessful, which saw the visitors emerge victorious.
The men from Port Elizabeth showed their intent early on with the team being denied a try in the 11th minute due to a knock-on, but Van Breda kicked their first penalty goal a minute later to earn the first points of the match.
Cronje touched down soon after as a chip in their own half was gathered neatly, which they followed up by some fantastic inter-passing to get over the chalk.
Ospreys tried hard to force their way over the tryline as the half progressed, but a combination of handling errors at crucial times and the visitors’ solid defence left them scoreless in the opening stanza.
Van Breda extended the Isuzu Southern Kings lead to 13-0 on the stroke of halftime with a long-range penalty goal, and he continued his fine goal-kicking three minutes into the second half with his third three-pointer of the match.
Ospreys finally opened up their account in the 52nd minute with Morgan Morris (No 8) diving over the tryline from a pick-and-go after sustained pressure up-front, and the successful conversion allowed them to reduce their deficit to nine points.
The Isuzu Southern Kings were dealt a big blow in the 65th minute as Cronje received a yellow card for infringing at a ruck following an earlier team warning by the referee, which saw the side being reduced to 14 men at a crucial time of the match.
The hosts took advantage of the extra man in the 71st minute with Hanno Dirksen (winger) cruising over on the outside after they spread the ball wide, and the conversion allowed them to trail the visitors by only two points with eight minutes left to play.
Ospreys had a golden opportunity to take the lead after being awarded a kickable penalty with a minute to play, and another after the regular 80 minutes of play, but both attempts were unsuccessful, which allowed the Isuzu Southern Kings to secure the historic 16-14 victory.
Ospreys 14 (0) – Tries: Morgan Morris, Hanno Dirksen. Conversions: James Hook, Luke Price.
Isuzu Southern Kings 16 (13) - Try: Erich Cronje. Conversion: Scott van Breda. Penalty Goals: Scott van Breda (3).