World champion Lewis Hamilton has been forced to withdraw from the first day of Formula One testing in Barcelona due to illness.
The Briton had started the session for Mercedes but managed just 11 laps before he had to call it a day as he was feeling unwell.
"An unplanned stoppage keeping us off track at the moment. Lewis Hamilton is unwell and not able to continue driving today," said the team on Twitter.
Mercedes said Hamilton will be replaced for the remainder of the session by Pascal Wehrlein, who was initially testing with Force India.
The young Mercedes reserve had completed 10 laps in the Force India before he had to make the switch to the Mercedes.
Force India said Sergio Perez will drive in the afternoon session.