Sainz took his second consecutive pole for 2023 in Singapore, and while the Ferraris still struggled to replicate their one-lap pace in the race, the Spaniard capitalised on Red Bull's off-weekend to break the latter's winning streak.
But while taking the first non-Red Bull win of the season was a much-needed tonic for Ferrari, Sainz cautioned that its SF-23 hasn't actually changed and still displays unpredictable handling traits ahead of a clean slate design for 2024.
"No, honestly there is nothing fundamental that has changed on the car since the beginning of the season," Sainz replied when Motorsport.com asked him if Ferrari has managed to cure its unpredictability.
"The car is still obviously not great in some areas, very good in others and there's certain tracks like Monza and Singapore that the car has adapted to very well, while there are other tracks like Zandvoort, Silverstone where it was very difficult to drive.
"It's still a tricky car and we're still trying to find the right set-up. We've been working hard to try and find the sweet spot and probably we still haven't found it yet.
"That's why every weekend I try something different in the car and it seems to be working, we seem to keep finding little ways to find a better pace. And with this, I don't mean more predictable, just find speed and lap time."
He added: "It is true that in the race even in Singapore we were nothing special, with tyre wear, tyre degradation it still has its weaknesses that we need to address."
Due to Ferrari's ebbs and flows, Sainz has given up on predicting where the Scuderia can replicate its Singapore performance, which was boosted by his track position and clever DRS tricks to keep Lando Norris and George Russell behind.
"I'm not sure. Looking at track characteristics, none of the tracks that are coming are anywhere close to Singapore or Monza, which are probably the two extremes," he said.
"It is impossible to tell which tracks are going to suit us.
"But still, the trend of being quick in qualifying and struggling a bit in the race is always going to be there."
When asked if Singapore was the blueprint for how Ferrari should execute a flawless race weekend, he said: "Yes, and I think we also need to give credit to the team.
"Okay, I did my job with the DRS and with the pace management, but everything else was executed very, very well.
"I still believe we didn't have the fastest race car in Singapore, and we still managed to win, which speaks highly of Ferrari and the race execution that we did.
"So, I think we can be proud of it and give a bit of recognition to the team. Now we can keep building that momentum and confidence in ourselves for next year."
