Hamilton race engineer Bonnington absent in Mexico and Austin

©Mercedes

Mercedes race engineer Pete Bonnington, the man who guides Lewis Hamilton on Grand Prix weekends, will miss the Mexican and US races to undergo a personal medical procedure in the UK.

Bonninton - or "Bono" - is the instantly recognizable voice on Hamilton's radio and the valuable strategist who has helped the Briton secure his four titles with Mercedes.

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"Bono is not in Mexico this weekend and will not be in Austin either owing to a medical procedure back in the UK," said a spokesman for Mercedes.

"Lewis will be engineered by Marcus Dudley, usually his performance engineer standing to Bono's right in the garage.

"Performance engineer for the two weekends will be Dom Riefstahl, who usually runs our race support operations in Brackley."

Hamilton has a reasonable shot of clinching his sixth world title in Mexico City, but if the 34-year-old secures the crown on Sunday it will be the first time Bonnington won't be present for the coronation.

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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.