Johannesburg - Izak van der Merwe secured the winning point for South Africa in the first singles match as he beat Slovenia's Blaz Kavcic 7-6 (3) 6-4 6-4 in their Euro-Africa group one Davis Cup qualifier at the Arthur Ashe tennis complex, in Soweto, on Sunday.
The victory meant that the South Africans advanced to the World Group playoffs for the fourth year in succession.
South Africa won the tie 4-1 with Van der Merwe responsible for three points for the home team following wins in the doubles alongside Raven Klaasen, and in the first day's singles match against Grega Zemlja.
In windy conditions against Kavcic, the first set was closely contested with Van der Merwe breaking the Slovenian in the sixth game as he gained momentum.
Kavcic, though, had other ideas as he broke straight back in the next game.
The set went to a tie break, and at 3-3 on Kavcic's serve, the wind got the better of the Slovenian as he nearly missed the ball completely in his first serve to send the ball out of play.
Van der Merwe won the point with Kavicic on his second serve, and the
South African proceeded to take the next three points in a row to win
the tie-break 7-3.
The second set went according to plan for the home team as Van der Merwe broke in the fifth game to take a 3-2 lead and with a service game coming up.
However, he found himself down 15-40 in the next game, but came back with two blistering aces and then another strong serve to win the game.
It proved to be the turning point as Kavcic had nothing left and lost the set 6-4 with Van der Merwe breaking early in the third set to lead 2-1.
South Africa's No 1 for this tie went on to win the set 6-4, and with it, clinch victory for the home team.
As Van der Merwe won his match in straight sets, the fifth rubber was played despite it not affecting the results.
Ruan Roelofse came out for South Africa and defeated Nik Razborsek 4-6, 6-3, 7-6 (7/2).
Razborsek took the first set 6-4, with Roelofse responding by winning the second 6-3.
The South African had the edge in the deciding set, winning the tie-break 7-2 to take the hosts to a commanding four points from five matches.