Oct.9 (GMM) Following the announcement of Alex Wurz's immediate retirement, Kazuki Nakajima will make his formula one race debut in Brazil next weekend, Williams said on Tuesday.

The 22-year-old test driver, rookie of the year in GP2 this year, has covered more than 7000 kilometres as the Grove based team's test and occasional Friday driver throughout 2007.

Williams insists, however, that pitting Nakajima alongside Nico Rosberg at Interlagos is to build his experience and "not an evaluation exercise for a race seat in 2008".

The announcement, however, coincided with speculation in the German press that Williams' engine supplier Toyota, which backs the son of former grand prix racer Satoru Nakajima, requested that Kazuki replace Wurz for the season finale.

It may even have resulted in a six-figure compensation payout for Wurz, the magazine Sport Bild claimed.

Sir Frank Williams commented in a statement: "You cannot assess a driver's capability on the basis of one race but this is an ideal opportunity to develop Kazuki's experience."