The rand was 14.4480 versus the greenback by 0814 GMT, 0.4pc weaker than the previous day's close.
An index measuring the dollar against a basket of six major currencies jumped to a six-day high of 97.343 and was last up 0.1pc at 97.302 after strong U.S. economic data.
The rand had already fallen a day earlier as recent gains over optimism about a preliminary US-China trade deal gave way to profit-taking and concerns about Britain's exit from the European Union.
Wayne McCurrie, of FNB Wealth and Investments, told Reuters while the rand had lost a couple of cents it has performed very well recently, bolstered by international events even in the face of problems with the economy and power supply at home.
"The specific little bit of weakness today, there is no news or event you can put your finger on," he said. "It's nothing in the bigger scheme of things."
Stocks were higher, with the Johannesburg Stock Exchange's Top-40 index up 0.89pc and the broader all-share index also up 0.79pc.
Government bonds were flat, with the yield on the benchmark 2026 instrument up 0.1 basis point at 8.3pc.