Poland's Robert Kubica will be replaced in Sunday's US Grand Prix by German teenager Sebastian Vettel after failing a medical, the BMW Sauber team said Thursday.

The governing FIA confirmed in a brief statement that Kubica, who crashed heavily in last Sunday's Canadian Grand Prix, was ruled out after an examination by the medical delegate at Indianapolis.

Kubica had told reporters earlier that he was 100 percent fit and ready to return.

"Naturally I'm disappointed because I felt absolutely ready to race," he said in a statement. "But I respect the decision. It was made because there is too much risk to let me race in this Grand Prix in case I have another impact so soon after Montreal."

Kubica's spectacular accident occurred when his car made contact with the rear wheels of Jarno Trulli's Toyota on the approach to the hairpin on lap 27 on the Gilles Villeneuve circuit.

The 22-year-old's car took off, flying through the air and slamming into the wall before barrel-rolling across the track. Kubica's feet could be seen through the sheared off front end of the vehicle.

BMW motorsport director Mario Theissen said Kubica will undergo another medical check before the French Grand Prix in Magny Cours on July 1.

Test and reserve driver Vettel, who will be 20 on July 3, will be the youngest man in Sunday's race and one of the youngest to start a Grand Prix since the world championship started in 1950.

"Of course I am looking forward to my first F1 race," said Vettel in a statement. "But I wish it had come under different circumstances.

"It's never nice if a team mate can't drive because he had an accident."

Only five other drivers in F1 history have made their race debuts at the age of 19, including double world champion Fernando Alonso [Images] with Minardi in 2001.

The youngest remains New Zealander Mike Thackwell aged 19 years and five months in the 1980 Canadian Grand Prix [Images].

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