Bottas suffered a broken exhaust during Q3 on Friday, and was told by the team to pull over and stop after telemetry flagged rising temperatures.
Despite not being able to complete the session he still earned eighth on the grid.
After inspecting the car the team realised that damage to the wiring loom and other systems was so significant that it was easier to swap to the spare chassis than attempt repairs.
Due to parc ferme the job didn’t get properly underway until Saturday morning. The team hoped to be able to complete the work and run in FP2, but in the end the work wasn’t completed in time, and thus Bottas missed significant dry running.
His original Ferrari power unit has been swapped over to the spare chassis, but he has had to take a new gearbox.
Under the current rules there are no grid penalties associated with any of the changes that the team was forced to make.
“We had an issue on the exhaust,” team boss Fred Vasseur told Motorsport.com. “And then we burned all the components around it, including the loom, and including the casing of the gearbox. The loom is going inside the chassis, and it's easier to change it."
"We expected yesterday to have to do it, but the car is sealed. Either you break the seals and you start from the pitlane, or you wait for this morning and you risk FP2. We hoped to make it, but we were too optimistic.
“The fact that we missed FP2, this is a shame. For sure, it would have been better to do the session, or we would always stay in the garage for FP2!”
Vasseur is confident that Bottas will not lose out too much after missing the dry running, as team mate Guanyu Zhou gathered some useful data.
“I trust him on the fact that the adaptation will be quite quick, and he will have a look at the data from Zhou, and have a good understanding. And he did some laps also yesterday on the almost dry conditions. So I’m not worried.”
Vasseur was encouraged by Zhou’s performance in qualifying, with the Chinese driver earning fourth in Q1, before he was caught out by a red flag in Q2 and had to settle for 14th.
"Zhou did very well in Q1, his lap in Q1 he would have been in Q3. It's a shame, but the target is to do Q2, and he did it again. And I think he's starting to improve step-by-step. I can't complain, he's doing a good job.
“I'm quite happy to be disappointed with Q3 and Q2, both of my guys could have done better results."
