Montreal - Safety concerns might force Manor driver Rio Haryanto to not fast at the Canadian Grand Prix on Sunday.
The Indonesian rookie is a strict Muslim, and therefore currently fasting - including not drinking water - between dawn and sunset.
Dehydration is a worry
But the Mirror newspaper quoted Haryanto's manager Piers Hunnisett as admitting that "Ramadan might need to take a back seat to safety" when it comes to Sunday's long and high-speed race on the Circuit Gilles Villeneuve.
Read: Canadian GP Qualifying - as it happened
Hunnisett said: "It's more of a safety issue.
"He has been following his faith in Montreal this week but we will see what the advice of the team doctors is. It is a long race and there is a worry about dehydration.
Hunnisett added: "Drivers lose a lot of body fluid during a race and we don't want him losing concentration when he is driving at 350km/h."
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