Williams has confirmed that Felipe Massa will continue to race for the team in 2017, ahead of Valtteri Bottas' impending switch to Mercedes.
Massa initially announced his retirement at last season’s Italian Grand Prix, bringing the curtain down on a career which yielded 11 wins and the runner-up position in the 2008 standings.
However, Nico Rosberg’s decision to retire as World Champion opened a vacancy at Mercedes, with the champions soon installing Bottas as its preferred choice.
Massa has now agreed a deal to end his short-lived retirement to continue competing for Williams, alongside 18-year-old rookie Lance Stroll.
"Firstly, I am very happy to have an opportunity to return to Williams," said Massa, who placed 11th in last year's standings.
"I always intended to race somewhere in 2017, but Williams is a team close to my heart and I have respect for everything it is trying to achieve.
"Valtteri has a great opportunity, given the turn of events over the winter, and I wish him all the best at Mercedes.
"In turn, when I was offered the chance to help Williams with their 2017 Formula 1 campaign, it felt like the right thing to do.
"I certainly have not lost any of my enthusiasm for racing and I’m extremely motivated to be coming back to drive the FW40.
"The support from my fans over the last few weeks has been a huge boost and I'm grateful for that.
"I also look forward to working with Lance; I’ve known him for many years and seen his talent develop during that time, so I look forward to seeing what we can achieve together."
Deputy Team Principal Claire Williams welcomed Massa's stay with the team and wished Bottas well for the future.
"I’m delighted that Felipe has agreed to come out of retirement to be a part of our 2017 campaign," she said.
"With Valtteri having a unique opportunity to join the current constructors’ champions, we have been working hard to ensure that an agreement could be made with Mercedes to give Valtteri this fantastic opportunity.
"Valtteri has been part of the Williams family since 2010 and in that time has proved a huge talent, securing nine podium finishes. I would like to take this opportunity to thank him on behalf of the whole team, and wish him a successful season as he joins Mercedes."
Mercedes is expected to announce the recruitment of Bottas shortly.
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