Alpine CEO Laurent Rossi has confirmed the team has lost a power unit from Fernando Alonso's pool after he retired from the Saudi Arabian Grand Prix.
The Spaniard showed strong pace in Jeddah and looked set to battle team-mate Esteban Ocon for a top-six finish before being forced to pull out of the race in the closing stages.
Addressing the issue experienced by the two-time F1 champion, Rossi told Auto Hebdo: "Fernando was able to continue driving and the engine was running but in obviously not ideal conditions. We preferred to stop it.
"The water pump was faulty. We have identified the cause of the problem.
"This is a problem with the freshness of the new system which is working for the first time and which we have not yet had the opportunity to validate, as is the case for all teams.
"The advantage is that it is neither structural nor intrinsic. The engine itself, its design, or the architectural choices made are not to be questioned, because the engine does what is expected of it."
Alonso engine "lost"
Each driver is limited to three power units for the season made up of various individual components before penalties are brought against them.
Explaining the loss of Alonso's first unit, Rossi added: "The problem is that this accessory [water pump] is integrated into the engine.
"The water pump eventually disintegrated and fell into the engine. If we had wanted to repair it, we would have had to break the seal.
"The engine is therefore lost to us. Even if its physical integrity is not directly affected, for us, it is one engine less."
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