Sebastian Vettel could not resist the lure of racing in the three-week gap between F1's Chinese and Spanish grands prix.
Kolner Express newspaper revealed that the Red Bull driver entered the German championship race at Ampfing in Bavaria with Michael Schumacher's KSM team.
The report said it was the reigning world champion's first kart race for three years.
And, confirming the news, the kart maker Tony Kart revealed that Vettel tested the machine at the Lonato track in Italy for two days before the German event.
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