Valtteri Bottas' progress in session one of F1 testing came to an abrupt halt this morning, as a transmission issue led to lengthy repairs on his Mercedes W12 car.
The Finnish driver only managed to complete one lap before being hampered by the problem. The team describes it as a gear shift issue, with the Brackley outfit opting to change the gearbox before investigating the original problem.
It's a worrying start for the reigning world championships, who already revealed to the media that there are some gremlins within the new power unit that still need to be resolved.
Once the gearbox is replaced, Bottas is expected to re-emerge from the garage, but with just three days of test running before the season gets underway at the end of the month, its hardly an ideal situation.
Mercedes updated fans on the current situation with a Tweet, which can be found below.