Former champions Williams hoped the last could be first again after finally unveiling their 2013 Formula One car on Tuesday at the Barcelona circuit where they were winners last year.

The last of the 11 teams to show off their new car, Williams hoped the FW35 would be an improvement on the FW34 that took Venezuelan Pastor Maldonado to their first victory in nearly eight years in May.

The Renault-powered FW35 represents a virtually all-new car compared to last season's FW34, Williams' technical director Mike Coughlan says.

The FW35 "is an evolution of the FW34 of 2012, it's better and more refined, with more than 80 percent new parts," Coughlan explained.

Maldonado, in his third season with Williams, will be partnered this term by 23-year-old Finn Valtteri Bottas, who has replaced Bruno Senna.

Team owner Sir Frank Williams said of Bottas, a test driver last season, "Valtteri is quieter but still waters run deep, and he is a highly gifted driver."

The 70-year-old Williams has high hopes for the FW35, saying, "A talented group of people with lots of imagination worked hard to produce the FW35. We believe it represents a step forward to last year's car which was already very competitive."

He is convinced his team can fight their way back this season to again "challenge the very best."

AFP - Global Times