Ferrari had explored the possibility of signing Adrian Newey following the celebrated designer’s decision to leave Red Bull in April.
But talks broke down in the summer and the 65-year-old is set to move to Aston Martin, who have scheduled a news conference for 10 September, when Newey’s new role is expected to be announced.
Ferrari started this season as the second fastest team, behind Red Bull. Carlos Sainz, who is being replaced by Hamilton, won the third race of the season in Australia before team-mate Charles Leclerc dominated the Monaco weekend to take a victory from pole position.
But Ferrari slipped in competitiveness during the summer when an upgrade to the car’s floor induced aerodynamic instability.
Changes to the floor aimed at eradicating this problem were introduced at last weekend’s Italian Grand Prix, where Leclerc took a home victory.
However, as the Monza track is not one where the high-speed “bouncing” issues suffered by Ferrari are usually encountered, the team have said they will need to wait for further races to discover whether the fix has worked.
The team lie third in the constructors’ championship, 31 points behind second-placed McLaren, who are eight adrift of leaders Red Bull.
Leclerc is third in the drivers’ championship, 86 behind the leader Max Verstappen of Red Bull and 24 behind McLaren’s Lando Norris.
The Ferrari car is on average the third fastest in qualifying over the 15 races so far this season, 0.293 seconds slower than Red Bull.