Kovalainen takes 'joker' engine change

The Finn had not yet taken his one permitted 'joker' engine switch this season, and the team opted to do so this morning after noticing some wear on Kovalainen's Mercedes V8.

"We have changed the engine in Heikki's car as a precaution," said Mercedes motorsport boss Norbert Haug.

"We saw a little bit of usage in the engine and this is a joker engine - so there is no grid penalty applied. The decision was taken yesterday."

Haug emphasised that the change was purely precautionary and would not have been undertaken without the 'joker' rule.

"If there was not a joker engine we would certainly have done nothing, and the chances that we would not have a problem are really high," he said.

"It is a critical time of the year and if you have it available you should use it. We have had very good reliability so far. If you see only a risk of one or two percent, maybe it is even less, then you should use it if you can."

Kovalainen's title-chasing teammate Lewis Hamilton still has his 'joker' change available.