Felipe Massa is not ruling out a switch to Formula E in the future.
In fact, the Brazilian looked set to switch to the electric single-seater series for 2017 before Valtteri Bottas suddenly vacated his Williams seat.
"After I decided to retire from F1 I did a test with Jaguar," Massa said.
"I think it's a fantastic series and I see a great future when I decide to stop F1."
Rumours are swirling that Williams could replace Massa with Fernando Alonso, Carlos Sainz or Sergio Perez for 2018.
Massa, 36, told Brazil's Globo: "I feel like I'm still competitive and so that is motivating.
"But it is true that I do not want to stay in F1 to be at the back of the grid."
The 2017 season continues with the Italian Grand Prix on Sunday.