World Rally champion Sebastien Ogier could be excluded from last week's Rally Mexico, pending an FIA investigation into his Ford Fiesta WRC's gearbox.
The Frenchman finished second in Mexico but his Fiesta was looked at in post-event scrutineering with a query raised over the gearbox, which Autosport understands could be underweight.
While the events from the third round of the world championship have been declared final, a footnote on the document reads: "Subject to further checks to be carried out by the FIA on the gearbox of car No 1."
The FIA has confirmed to Autosport that the gearbox has been sealed and will be taken from M-Sport to France where FIA technical Jerome Toquet will inspect it further.
Nobody from M-Sport was available for comment.
Toquet will make a report to the Rally Mexico stewards, who will then make a decision. It is expected to be known before the start of the next round of the championship, the Tour de Corsica, on April 6.
One source told Autosport: "Jerome will be looking at tolerances, he might well look at other gearboxes as well.
"This decision to investigate further infers there wasn't enough time to really get to the bottom it at post-event or it could mean there was a very strong defence from the team and that defence required further investigation.
"In terms of penalties if the car is found in contravention of the regulations, it could be anything from a time penalty to exclusion."
If Ogier is excluded, he would lose his eight-point lead of the series and slip to third in the standings behind Toyota driver Jari-Matti Latvala and M-Sport team-mate Ott Tanak.
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