South Africa will play in the Euro-Africa Group I division of the Davis Cup again next season after they lost to Canada in their World Group playoff in Montreal on Sunday.
The underdog South Africans, who had put up a valiant fight to win the doubles rubber, were eventually halted by world number 15 Milos Raonic.
Raonic beat the SA team's top-ranked player, Izak van der Merwe, 6-2, 6-2, 6-4 on the final day as the hosts won the tie 3-1 with a match to spare.
Van der Merwe and doubles specialist Raven Klaasen had kept the tourists in contention with a 6-4, 7-6 (7/3), 7-6 (7/5) victory over Vasek Pospisil and Daniel Nestor on Saturday.
On the opening day, however, Van der Merwe had gone down to Pospisil and gutsy debutant Nikala Scholtz had narrowly lost to Raonic to put South Africa on the back foot.
Canada retained their place in the elite World Group, while the South Africans were defeated in the playoffs for the fourth year in succession.
South Africa were without the country's top-ranked player, Kevin Anderson, who made himself unavailable for the tie, and Davis Cup veteran Rik de Voest, who injured his wrist on the eve of the playoff.