Mercedes have changed a component on Lewis Hamilton's power unit ahead of Sunday's title-deciding Abu Dhabi Grand Prix.
It has been confirmed in the Technical Delegate's Report from the FIA that the team are running a new exhaust system for the remainder of the weekend.
This move does not incur a penalty. The report says that Hamilton has previously used four exhaust systems during the season.
"The exhaust system used by Lewis Hamilton is one of the eight new exhaust systems allowed for the 2021 Championship season and this is in conformity with Article 23.2a of the 2021 Formula 1 Sporting Regulations," a note reads.
Hamilton sets the pace in P3
News of Hamilton's change of exhaust system was confirmed just as Free Practice 3 got underway, a session in which the Briton went on to top the timesheets.
Hamilton finished the final practice session of the year two-tenths clear of title rival Max Verstappen, with Valtteri Bottas half a second back from the championship contenders.
Verstappen and Hamilton go into Sunday's race on equal points, meaning that it is very much all still to play for.
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