Lewis Hamilton was forced to miss his Thursday commitments in Shanghai after suffering with symptoms of an allergy.
Having arrived in Shanghai for this weekend's Chinese GP, round three of the Championship, the 28-year-old visited the track before being sent back to his hotel by his team.
According to the Daily Telegraph, Hamilton's "ailment was said by Mercedes to be afflicting his eyes and nose and to require a period of rest ahead of Sunday's race. Shanghai has been affected by serious air pollution levels in recent weeks."
The newspaper added that Hamilton was due to be seen by a doctor late on Thursday evening.