Mercedes had hoped that running Hamilton on a longer opening stint in Japan would pay off at the end of the race, but the SF90 still proved too quick to get by.
Explaining the move, trackside engineering director Andrew Shovlin said on Mercedes' YouTube debrief: "The simple answer is [Hamilton ran longer] to create an offset with the tyre degradation to Vettel.
"As you saw, Lewis comes out a fair gap behind Vettel but he's on fresher tyres and fresher tyres all the way to the end of the race so that gap gets closed down.
"We can put that data into our models and we know how the tyres degrade, and the cost over the entire race was two and a half seconds, but if you can get tyres that are much quicker when they are fresher that is what allows you to overtake.
"We also need to make our car better at overtaking because the Ferrari is a very difficult car to pass.
"You will have seen at a lot of the recent races we can catch up with them and we are quicker in the race than them but what we can't do is get past if we are behind. That we're going to work on."
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