Lewis Hamilton's first day of testing for Mercedes has been cut short due to illness.
The 2014 world champion was in the car on Thursday morning but completed just 11 laps in the opening two hours before the team announced he was not well enough to continue.
Reserve driver Pascal Wehrlein - who was already driving for Force India - is taking over the W05 for the rest of the opening day. Wehrlein had been scheduled to drive for Force India on both Thursday and Sunday at Barcelona. Force India is likely to put Sergio Perez back in the VJM07, with the Mexican already at the Circuit de Catalunya.
Hamilton is supposed to drive for Mercedes again on Saturday, with Nico Rosberg in the car on days two and four.
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