Lewis Hamilton's near-retirement at Sepang leaves Ferarri desperate for answers

The power-unit glitch struck several cars after the rain delay at Sepang although the Ferrari-powered cars were among the worst affected, and at one point Hamilton looked close to retiring.

Hamilton was due to start second, but he ground to a halt on the start-finish straight and had to restart his car on track. GPblog has already covered how the FIA's software lockdown was triggered, however, what had been missing until now was Ferrari's own account.

At the post-race press conference, Vasseur claimed to not know what had gone wrong.

He did reveal how far the fix reached and the FIA asked the teams to change the software on all 22 cars. The background was the wet-weather setting the FIA has used since the start of the season, which cuts the electric motor's output from 350kW to 250kW in wet conditions. Teams had to re-upload FIA-supplied wet-weather code to their power units before the new start, as GPBlog had explained, causing chaos at the start of the race.

Vasseur explained that one stricken car would have had very different consequences.

Because six to eight cars were affected, race control stopped the formation lap. Vasseur said he was unsure whether "luckily" was the right word for that but dealing with the same problem mid-race would have been much harder. "But we still need to understand exactly what happened," Vasseur added.

The FIA's Nikolas Tombazis later explained that it came down to circumstance, because not every car dropped to the same low speeds, so the problem has not been as obvious.

Hamilton did not hide how it felt in the car. "There was 'total panic,'" he said afterwards. He also told reporters that he had never before had to pull over, switch off the car and restart it.

His afternoon did not get any easier after that. Ferrari started him on slicks while most of the field chose intermediates, which dropped him to P17. He fought back to finish third, behind winner Max Verstappen and Kimi Antonelli.

That leaves Ferrari with an open question for the next race. Thunderstorms are forecast in Singapore, and the team still has no full explanation of why its cars stalled at Sepang.

If the wet settings catch out Ferrari-powered cars again, it could happen in a race, not on a formation lap.