Toro Rosso's striking new STR12 hit the tarck this morning in Barcelona, but the Faenza-based outfit will be aiming for mileage rather than speed on its first day of running.
Undoubtedly one of the best looking cars of the 2017 crop, the STR12 nevertheless encountered an ERS issue with its Renault power unit during its film day at Misano last week.
But Carlos Sainz isn't concerned with any reliability issues affecting the new car.
"Hopefully, we can have no issue and cover kilometres as this is the first week of testing," Sainz said.
"I will be looking more at the lap count than the lap time itself. This first week, we need to be patient and understand the new regs."
Toro Rosso tech boss James Key praised Renault for its winter work and expressed his satsifaction to be working once again with the French manufacturer.
"Renault has done a great job, the new engine is a great leap forward," key said.
"It's great working with Renault again actually - they're in good shape at the moment. We're looking forward to a developing engine. That's something we've missed the last two years."
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