Sebastian Vettel was seen wearing gray boxers over his race suit as he saw his team in the pit lane. The footage was caught on camera moments before the first practice session at the new Miami track.
The four-time champion appeared to laugh before waving his hands in a confused gesture. It comes after FIA bosses announced a crackdown on jewelery and fire-proof underwear from this weekend.
The rule means fire-proof underwear will now be checked in scrutineering with teams required to confirm their drivers were compliant with the rules. Failure to follow the guidelines may result in drivers issued fines or even period penalties.
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He said: “I feel like it’s almost like a step backwards. If you think about the steps we are taking as a sport. All the more important issues and causes we need to be focused on.”
“It’s a small thing. I’ve been in the sport for 16 years… in the car I only have my earrings on and my nose ring, of which I can’t really remove. It seems unnecessary for us to get into this late.”
However, new race director Niels Wittich issued another warning to teams about the issue in his pre-event notes for Miami.
He said: “Metallic objects, such as jewellery, in contact with the skin can reduce heat transmission protection and thus may increase the risk of burn injuries in the event of a fire. The wearing of jewelery during the competition can prevent both medical interventions as well as subsequent diagnosis and treatment should it be required following an accident.”