Venezuelan Pastor Maldonado will race for Williams again next season with Finland's Valtteri Bottas handed the role of reserve, the Formula One team said on Thursday.
There was no mention of the team's second race driver, with Brazilian veteran Rubens Barrichello hoping to compete in his 20th season next year but facing strong competition for the seat.
Maldonado, a former GP2 champion who brings considerable funding to the team from his country's state oil company PDVSA, scored just one point in his rookie season to Barrichello's four.
He had been expected to stay on but Williams triggered some uncertainty when the official entry list was published on Wednesday with the team having no drivers confirmed.
Last season was the worst in the history of one of Formula One's most successful teams, with Williams finishing ninth overall.
Principal and founder Frank Williams said Maldonado had shown his potential nonetheless and would play an important role.
"Pastor has proven he is not only quick but also that he is able to maintain a consistent and strong race pace," he said on the team website (www.williamsf1.com).
"Pastor has been responsible for all of our forays into Q3 (the final top 10 phase of qualifying) in 2011 and his race at Monaco was outstanding ... he will play a critical role in 2012 as we rebuild the team and move forward."
Maldonado, who crashed out in Monaco while in sixth place and scored his sole point with a 10th place in Belgium, said it had been a tough season for the whole team but he would learn from it.
"I am convinced the steps we have taken to improve our competitiveness will bear fruit in 2012 and beyond. I am thrilled to be part of that and also to represent the people of Venezuela in Formula One."
Williams hinted Bottas, 22 and winner of the GP3 series this year with four wins in the last seven races, was not ruled out of competing for the team next year as well as taking part in Friday practice.
"We anticipate that Valtteri will participate in a Friday practice session at 15 grands prix next year, most likely with a more experienced driver taking over for the remainder of the race weekend," he added.
"We will announce the identity of that driver in due course."
