Williams is set to complete its 2012 Formula One race driver line-up after Bruno Senna signed a contract.
Italy's Autosprint cited "Brazilian sources" in reporting that the former HRT F1 and Lotus Renault GP driver, whose famous uncle Ayrton Senna died at the wheel of a Williams in 1994, will replace Rubens Barrichello and become Pastor Maldonado's new team-mate.
"The commitment should be official within the coming days," said the report.
Autosprint said Senna has amassed an impressive EUR14 million in major Brazilian sponsorship, including OGX, an oil giant headed by billionaire Eike Batista.
The deal reportedly also includes team sponsorship by 28 year old Senna's sponsors Embratel and Gillette.
Autosprint said Force India refugee Adrian Sutil had been in contention for the seat, but the reduction in value of his Medion sponsor backing "was crucial".
The unofficial news was also reported by the Brazilian Grande Premio website, who said Senna signed the contract in the UK on Monday.