Renault's Giancarlo Fisichella will lose 10 places on the Belgian Grand Prix starting grid after an engine change on Saturday.
A spokesman confirmed the change, a blow for the championship-leading team's hopes of repeating their double podium finish in the previous Italian Grand Prix and a boost for rivals McLaren.
Renault lead McLaren by eight points in the constructors' championship, with four races remaining including Sunday's final European round.
Fisichella's Spanish team mate Fernando Alonso can, however, become Formula One's youngest champion if he beats McLaren's Kimi Raikkonen by four points at Spa.
The team had detected a problem with the Italian's engine after Monza but had delayed replacing it until they had completed more mileage. Heavy rain then washed out most of Friday's practice.
Under Formula One rules, engines must last for two races and any unscheduled changes incur a starting penalty.
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