Brazilian driver Felipe Massa has pulled out of the Hungarian Grand Prix due to illness and will be replaced by reserve Paul di Resta for qualifying later Saturday and for Sunday's race.
The Williams team said in a statement that the 36-year-old Massa went to the Formula One medical center and then Honvedkorhaz hospital on Friday for ''precautionary tests'' after feeling ''unwell and dizzy'' during the second practice session.
Although he was cleared to take part in Saturday's third and final practice run, he again felt unwell and made the decision to withdraw after clocking the 17th time out of 20 drivers.
Williams says it ''supports Felipe's decision and the team will work with him to ensure he makes a full recovery, with a view to return to the race track for the Belgian Grand Prix'' in late August.
Di Resta will race alongside 18-year-old Canadian driver Lance Stroll.
For the 31-year-old Di Resta, it is an unexpected chance to get back behind the wheel in F1. The last of his 58 F1 races was the Brazilian GP in November 2013.
In three seasons with the Force India team, he had a best result of fourth at the Singapore GP in 2012 and at the Bahrain GP in 2013.
Di Resta had not driven the Williams F1 car on track before and had very little time to prepare.
Deputy team principal Claire Williams said before qualifying that Di Resta would be ''a bit nervous'' about driving on the Hungaroring circuit.
Qualifying is split in three sessions, with five drivers eliminated after the first and another five after the second to leave the last 10 to battle it out in the third.
Although Di Resta failed to make it into the second, and qualified only 19th out of 20 drivers for Sunday's race, his team hailed it over the radio as a ''fantastic effort.''
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