Mercedes has been forced into making a complete power unit change, impacting Kimi Antonelli’s running on the second day of the opening test in Bahrain. 

The Silver Arrows discovered an issue with the power unit it was running, and following an investigation has decided to complete a full change. 

As a result, Mercedes has confirmed that Antonelli will not be back out on the circuit before lunch.

On the opening day on Wednesday, Mercedes completed only 85 laps with it being impacted by a suspension problem.

Antonelli failed to even complete a lap on Thursday, marking a major setback for the Italian and the Brackley-based team.