Guess who knocked on Alonso's door at 6am?

Fernando Alonso got a knock on his door at 6am this morning, with the McLaren driver opening to a smiling representative of the World Doping Agency.

Doping officers are allowed to turn up without notice at an athlete's house or hotel, with rules obliged to inform the agency of their exact whereabouts, where they happen to be in the world.

Alonso, who testing at Aragon this week with the Toyota LMP1 WEC team, gladly fulfilled his duties and even posted a picture of the impromptu visitor on Instagram.

Another venture, another new helmet for Fernando

The two-time world champion is the second F1 driver to be monitored by the doping agency this week, with Romain Grosjean also getting a 6am knock on his door on Monday.

Fortunately, F1 enjoys a clean record when it comes to doping, and while controls have been scarce in the past few years, they have become more frequent recently, with Red Bull's Daniel Ricciardo revealing that he had been tested in December, on Christmas day!

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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.