No Renault F-duct in Germany or Hungary

An F-duct system will not be seen on Renault's 2010 car until the Belgian grand prix late next month.

Robert Kubica said he is worried about Hockenheim this weekend, because the absence of the downforce-stalling concept means Renault is having to run less rear wing to keep up with the other cars.

"This could cost us in the corners," said the Pole.