“On Tuesday and Wednesday [Sebastian] Vettel is coming, which will be a good comparison for me. Three months ago he was better than me by two tenths, but I am in better form now because I have more experience.”

Bourdais' manager Nicolas Todt, meanwhile, has claimed that Toro Rosso is eager to keep the record-breaking former multiple Champ Car king on-board for a second consecutive season, after the 29-year-old displayed increasingly impressive form towards the end of his rookie campaign in 2008. The only issue, he admitted, is budget.

“Toro Rosso wants to keep him,” the son of former Ferrari team principal Jean Todt told French magazine Auto Hebdo, “but the economic context is really difficult at the moment, therefore it is not really in our control.”

Todt was also insistent that the recent departure of co-owner and Bourdais supporter Gerhard Berger and re-sale of STR to parent company Red Bull 'doesn't change anything in a big way', adding: “Of course it is no simpler now, but also no more complicated.”

The 2009 STR4 is to again be designed by Red Bull Technology and built in Italy, and will be ready to hit the test tracks at the end of February, a month before the season curtain-raising Australian Grand Prix in Melbourne.