Red Bull driver Verstappen used the French manufacturer's latest spec at Marina Bay, despite Renault having warned that there were reliability risks involved.

Neither the works Renault team nor customer McLaren used the Spec C in Singapore, and both Verstappen and team-mate Daniel Ricciardo were hit by mapping issues during the weekend.

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Abiteboul said the result was a good indicator of the potential of the power unit.

"It's quite a good reward for all the effort put into the Spec C, which we know is not perfect given the circumstances," Abiteboul told Autosport.

"But we can see it's capable of delivering a healthy increase of 15kW, which was the expectation, and that's exactly what's happening.

"I think Daniel has found some way to work around some of the limitations of the mapping. Maybe Max after the weekend has also found his way.

"But let's be honest, it's not up to the drivers to find a way to work around the engine, it's up to us.

"However, it was clear that the Spec C was coming with a certain number of risks, and as always we would expect that this agreement is respected by everyone."

Although Red Bull has indicated that it may revert to the Spec B for the next race in Russia, Abiteboul is confident the Spec C will be optimised.

"Absolutely, mapping will be addressed," he said. "But mapping is also a factor of every single track we go to, and we'll try to see how we can explore that, and try to do a better job with Red Bull."

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