Lewis Hamilton could be facing a challenging weekend in Abu Dhabi as a result of damage sustained by his Mercedes engine in Brazil.
In hindsight, the Brit's 72nd career win at Interlagos was considered a small miracle given that Mercedes' engineers had predicted an "imminent failure" of his engine early on in the race following an exhaust issue and rising temperatures.
The unit ultimately survived, thanks in part to some handy remote work from a crew back at Brixworth, but an initial post-race diagnosis revealed damage, the extent of which is not yet known.
"God only knows how you can fix hardware that's just about to break and make the car finish," said Mercedes boss Toto Wolff.
"That race was just a nightmare until the chequered flag came down, and everything broke loose."
As a consequence, Hamilton could be forced to take on new engine components next week at Abu Dhabi, changes that would entail a grid penalty, or run with an older unit that could carry some reliability risk.
"If we just go back a little bit and look at what happened in the race, after the first pit stop with Lewis we noticed quite a significant problem, which required a huge amount of input from a number of sources," explained Mercedes chief strategist James Vowles.
"We have a team back in the UK at Brixworth who work alongside us on the intercom, and we have a huge team trackside working together diligently to understand what we can change on the engine to get to the end of the race.
"They did a fantastic job. It wasn't one change, it was a huge number of changes across a 40-50 lap period, where they were working with Lewis to adjust various componentry and get that power unit to the end of the race. They did a fantastic job," he added.
"The net result of that, though, is that the engine has sustained some level of damage, but we don't yet understand what.
"It has to be inspected and understood before we can make any decision going forward to Abu Dhabi."
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