Moreover, lower opening in domestic equities also weighed on the domestic currency, dealers said.
The dollar was weak against major global currencies, capping the rupee losses, they added.
The rupee had lost 4 paise to close at 66.73 per dollar in yesterday's trade on firm demand for the American unit from importers.
Meanwhile, the benchmark BSE Sensex was trading lower by 98.89 points or 0.38 per cent to 25,431.22 in early deals.