Nicholas Latifi looks set to replace Robert Kubica at Williams for 2020.
Kubica, having returned to Formula 1 this year but clearly struggling, said at Monza that he doesn't know if he has done enough to keep the race seat.
Williams has kept supporting the 34-year-old despite his struggle, but boss Claire Williams said at Monza: "We're working out what we're going to be doing from a race driver perspective for 2020 at the moment."
George Russell already has a Williams contract for 2020.
And Charrel Jalving, a well-connected motorsport marketing expert, has reported from Monza that the Latifi deal for 2020 is now done.
"Another great bag of money for Williams to continue to survive," he said.
Indeed, 24-year-old Latifi's father Michael is a billionaire and McLaren co-owner.
Latifi is already Williams' reserve and Friday driver, and he looks on course to qualify for his F1 Super Licence for 2020 by doing well in Formula 2.
"At the end of the summer, we'll know where he is," Michael Latifi said in June.