Raikkonen struck by engine failure in practice.

Kimi Raikkonen's prospects in the French Grand Prix were compromised by an apparent engine failure just a few minutes into the afternoon practice session at Magny-Cours.

The Finn pulled off the circuit with a trail of smoke coming from the rear of his McLaren-Mercedes and, if the problem is confirmed as a full-on failure - rather than an oil leak or similar - he will have to take a new engine for qualifying and accept a ten-place penalty when the grid is decided on Saturday afternoon.

Raikkonen is due to run eighth to last in the timed session, having been classified eighth - as the second best qualifier among those who pulled out - at Indianapolis, and, after McLaren's strong recent performances, was tipped to challenge for pole position as he attempts to close the gap on points leader Fernando Alonso.

Interestingly, Kimi had a new engine for this weekend, and he let slip on Thursday that it was of a new specification. Since team-mate Juan Pablo Montoya still has his Indy engine under the two-race rule, it must be assumed that the Colombian's is of a different spec and, therefore, perhaps not as vulnerable to failure. The three McLarens, headed by reserve driver Pedro de la Rosa filled places one, five and eight in opening practice, having, at one point, dominated the top three.

McLaren now has to decide whether to run Raikkonen to a normal qualifying strategy and hope that he can qualify first, and therefore start eleventh, or perhaps give him more race fuel and perhaps risk him starting even further down the field.