Jan.10 (GMM) McLaren's newly launched car, the MP4-23, made a trouble-free and fast debut on Wednesday at the start of a three day exclusive test session.

Following Monday's launch in Stuttgart, Pedro de la Rosa took the same chassis onto the Spanish circuit shortly after 9am, with Heikki Kovalainen joining him in action in a second completed MP4-23 in the afternoon.

"The first impressions of the new car are good," said Finn Kovalainen, who was also making his debut in a Mercedes-powered car after starting in formula one with Renault in 2007.

His best lap time was nearly a second slower than de la Rosa's, who went marginally faster than the 2007 car had managed at Jerez last month.

"The car's performance today is definitely an encouraging starting point," Kovalainen noted.

To the German newspaper Bild, Mercedes-Benz's Norbert Haug added: "The performance was a good sign, if you look at the lap time done with last year's car."