Highly-rated technical director James Allison is leaving Lotus and will be replaced by Nick Chester, the Formula One team said yesterday.

The announcement before the first race of the European season in Spain this weekend will be seen as a blow for Finnish Lotus driver Kimi Raikkonen, the 2007 world champion who is second in the standings to Red Bull’s Sebastian Vettel.

Allison has been with British-based Lotus, previously Renault, since 2005 after previous stints in the 1990s when they raced as Benetton.

No details were given about his likely destination, although early speculation focused heavily on Ferrari.

Allison worked for the Italian team for five years – during Michael Schumacher’s dominant years – overseeing trackside aerodynamic operations prior to joining Renault.

Chester was previously Lotus’s engineering director. He worked for the now-defunct Arrows before moving to the Enstone factory in 2000.

“He is already directly involved with this and next year’s cars, ensuring a smooth transition which has been underway for some time,” said team principal Eric Boullier.

“The 2014 technical regulation changes present many challenges, while our current position of second place in both the constructors’ and drivers’ world championships mean we cannot lose sight of this year’s development battle,” he added.

“Nick really has his work cut out, but we know he is more than capable of handling the tasks ahead.”