Apr.30 (GMM) Lucas di Grassi has admitted that even his continuing role at Pirelli is not a ticket back onto the F1 grid.
"I'm in the best possible position technically, as the driver with knowledge of the tyres - almost choosing them for next season - it puts me in a very comfortable position.
"Of course I want to race again with a team and I'm working on it," said the 2010 Virgin driver, who was replaced by the now Marussia team with Jerome d'Ambrosio at the end of his only season in F1.
"The only problem is the lack of sponsorship," di Grassi is quoted by Globo. "Let's hope some Brazilian companies want to come in to support."
Martin Brundle, a former F1 veteran whose son Alex now competes in the lower-tier GP3 series, admitted sponsorship is a problem for aspiring racers.
"Drivers are paying as much as $10 million to be a reserve at some teams," the British commentator told the Daily Mail.
"Nine men who raced in F1 last year don't have a drive any more. As soon as the money runs out, they're replaced by someone who does have money."