Cape Town - Kevin Anderson’s Shanghai Masters campaign ended in a second round loss to Germany’s Jan-Lennard Struff on Wednesday.
Struff, ranked 58th in the world, beat the South African No 1 in two tie-break sets, 7-6 (7/5), 7-6 (7/2).
Anderson, the current world No 15 and ranked 11th in Shanghai, had entered the clash on the back of a convincing 6-3, 6-1 first round win over Frenchman Adrian Mannarino.
Anderson had won his only previous encounter against Struff - 7-6 (8/6), 6-1 in Auckland in 2015 - but unravelled on the big points on Wednesday.
The loss will be a blow to Anderson’s chances of reaching the prestigious year-end ATP Finals in London, where the world's top eight players compete.
At the beginning of the week, Anderson, this year's US Open beaten finalist, was 10th in the race to London.