The Singapore winner will start the Suzuka race from sixth place, lining up two places behind his team-mate Charles Leclerc.
Sainz said that the knowledge that the car might be less competitive at Suzuka encouraged him to try different things on set-up in order to “challenge” both himself and the car.
When that didn’t work he took a step back to a more conservative approach, but he conceded he was “distracted” by the swapping around and didn’t have enough time to get fully comfortable with the changes.
“We knew before coming here that this track would expose us a bit more,” said the Spaniard.
“Probably with the high-speed characteristics, but also the long corners, high winds like we're having today, it was never going to be easy.
“I took the approach yesterday and this morning to try different things on the car, try to change the balance quite a bit, and try different things on set-up to try and put the car a bit in a different place.
“By the time of quali I saw that it was not quite working, and we had to go back to a more basic set-up, which in the end probably ended up compromising my quali preparation and my weekend in general.
“But I'm happy to try those things, and now focus on tomorrow, see if we can do a good race. I don't think we could have done much more because honestly the McLarens and the Red Bulls this weekend, they look one step quicker.”
Source: Autosport