Kimi Raikkonen's race engineer at Ferrari has left the team just six weeks before pre-season testing for the 2018 season begins.
David Greenwood has been the Finn's race engineer since he joined Ferrari in 2015 following a move from Marussia where he held the position of chief engineer, but has cited personal reasons for his departure and he will now return to the UK.
It's expected Greenwood will take up a role with Manor Racing's World Endurance Championship programme as the British squad looks to step up to the LMP1 category as a privateer entry running Ginetta's new prototype.
There has been no confirmation as to who will replace Greenwood as Raikkonen's race engineer, but with testing just weeks away and the launch of Ferrari's 2018 car scheduled for February 22, an announcement is expected soon.