Vettel at the risk of a grid penalty after red-flag violation!

Sebastian Vettel may suffer a serious set-back if the US Grand Prix stewards decide to hit the Ferrari driver with a grid drop penalty following a red-flag offence in FP1.

Friday's first free practice session was interrupted when Sauber's Charles Leclerc spun and then rejoined the circuit, projecting gravel on the track and forcing a red flag and a subsequent clean-up by the marshals.

Hamilton splashes his way to the top in wet Austin FP1

Vettel failed to slow sufficiently during the red-flag period, a clear breach of Article 31.6 of the F1 sporting regulations. The German was summoned to the stewards to be heard.

As a reminder, Force India's Esteban Ocon was hit with a three-spot grid penalty for a similar offence in Japan twi weeks ago, during Saturday's FP3 session.

Gallery: The beautiful wives and girlfriends of F1 drivers

Keep up to date with all the F1 news via Facebook and Twitter

Phillip van Osten

Motor racing was a backdrop from the outset in Phillip van Osten's life. Born in Southern California, Phillip grew up with the sights and sounds of fast cars thanks to his father, Dick van Osten, an editor and writer for Auto Speed and Sport and Motor Trend. Phillip's passion for racing grew even more when his family moved to Europe and he became acquainted with the extraordinary world of Grand Prix racing. He was an early contributor to the monthly French F1i Magazine, often providing a historic or business perspective on Formula 1's affairs. In 2012, he co-authored along with fellow journalist Pierre Van Vliet the English-language adaptation of a limited edition book devoted to the great Belgian driver Jacky Ickx. He also authored "The American Legacy in Formula 1", a book which recounts the trials and tribulations of American drivers in Grand Prix racing. Phillip is also a commentator for Belgian broadcaster Be.TV for the US Indycar series.