At 1602 GMT, the rand traded at 18.1275 against the dollar, around 0.42% lower than its previous close.
The dollar index, which measures the currency against six rivals, was last up 0.65% at 101.63.
Despite being on a rate-hiking cycle, the U.S. central bank has made little headway in returning to its inflation target of 2% and therefore would need to move interest rates higher still, Federal Reserve Governor Christopher Waller said.
However, analysts say investors are pricing in the probability that the Fed will need to cut rates later this year on an expected slowdown.
"Regardless of what these Fed governors say... eventually, as the economy slows down, they're going to have to start reducing rates," said Sasfin equity strategist David Shapiro.
Like most emerging market currencies, the risk-sensitive rand often takes cues from global drivers such as U.S. monetary policy, in the absence of major local economic data points.
South African investors will turn their focus next week towards March inflation figures to gauge the health of the local economy.
On the Johannesburg Stock Exchange, the blue-chip Top-40 index closed up 0.59%, while the broader all-share index ended 0.52% higher.
The government's benchmark 2030 bond was weaker, with the yield up 6 basis points at 9.945%.
(Reporting by Tannur Anders and Alexander Winning; editing by Jason Neely, Bhargav Acharya)
