Eventually, the car was appropriated by the newly formed Brawn GP team, and modified to accommodate a Mercedes-Benz engine in place of the expected Honda engine. Jenson Button performed its shakedown – the car featuring white, fluorescent chartreuse yellow and black colours. The team gave the BGP 001 its first test at Circuit de Catalunya on 9 March 2009, topping the timesheets many times. With the testing moving to Circuito de Jerez, Brawn GP continued to set the pace, finishing the test leading two of the three tests. During an interview Brawn said there was more speed to come after he explained that '...The BGP 001 car is the result of 15 months of intensive development work and the team have been nothing less than fantastic in their commitment to producing two cars in time for the first race'. At the first race an official complaint was launched by four teams against the rear diffusers of the Williams FW31, Toyota TF109 and the Brawn BGP 001 on the grounds that they did not fall within the dimensions set out in the regulations, but after analysing the cars the race stewards reported that the cars were legal. This ruling was appealed and the appeal was heard after the second race of the season. However motorsport's governing body ruled that the car was legal. There was another complaint at Malaysia after which BMW Sauber joined the appeal after they were deemed legal, again. After the appeal the diffuser was deemed legal by the FIA. In Spain, the car received its first upgrades since Australia which were mainly to do with the different cooling requirements of the Mercedes engine and gave Brawn a 1–2, just as in Melbourne.