DS Virgin driver Jean-Eric Vergne appears highly unlikely to take part in Saturday's Buenos Aires ePrix through illness.
The Frenchman was taken ill overnight and could be replaced by local hero and WTCC champion Jose Maria Lopez.
The team is yet to confirm whether the Argentinian will partner Sam Bird in Vergne's usual Virgin DSV-01 car.
Lopez, a works Citroen driver in the WTCC, is in town doing PR work for the brand.
He is currently in discussions with FIA Formula E officials to ensure he has the correct and necessary licence to compete.
Vergne is not taking part in Saturday morning's first free practice.