A report in the German media claims that Toro Rosso carried out a secret rolling road test shortly after the final pre-season test in Bahrain.

According to AutoBild, the Italian team carried out the test on AVL's rolling road, the company being an Austrian-based automotive consulting firm and independent research institute which is also - according to Wikipedia - "the largest privately owned company for the development of powertrain systems with internal combustion engines (ICEs) as well as instrumentation and test systems and also produces electric powertrains".

News of the 'test' came to light when anonymous letters were sent to the FIA, Ferrari, Mercedes and Sauber accusing a "Red Bull-Renault" team.

It is understood that Red Bull has said it did not carry out the test, though the denial only cites the fact that the RB10 wasn't used, thereby shifting the spotlight to sister team Toro Rosso which this year switched from Ferrari to Renault power.

In fact such a test is not strictly illegal however certain conditions have to be met including the removal of front and rear wings as no aerodynamic measurements are allowed.

Both teams had torrid experiences at the pre-season tests, as did all the Renault powered outfits, Toro Rosso completing 1,530 miles in all three tests - compared to Mercedes 3,086 miles - and champions Red Bull completing just 1,059.

Chris Balfe