
The team announced on Tuesday that the Williams test and reserve driver Nakajima will be the team-mate of German Nico Rosberg at the Sao Paulo race. The Austrian Wurz quit the team with immediate effect on Monday.
Team boss Frank Williams said that Nakajima's hopes of a driver's seat in 2008 won't depend entirely on his Brazil result.
"You cannot address a driver's capability on the basis of one race, but this is an ideal opportunity to develop Kazuki's experience. I am confident he will approach the race in a very workmanlike and focused way," Williams said.
Nakajima said: "This is a chance I intend to grab with both hands and repay the faith the team are showing me with a strong performance."
Williams lie fourth in the constructors' standings with 28 points. Rosberg garnered 15 for ninth place and Wurz is 12th with 13 points. Wurz was on the podium in third place at the Canadian GP on June.
Nakajima has raced in the GP2 series and took part in F1 Friday practice on five occasions this season.
DPA