One-lap form will be especially important in Baku as the sprint event will have its own qualifying session on Saturday, so drivers and teams will have to get it right twice.
Ferrari had the second-fastest car over one lap in both Bahrain and Jeddah behind Red Bull, but it stumbled in Melbourne, where both Mercedes and Aston Martin were ahead.
Vasseur says that the team has to concentrate on optimising its own performance and not be distracted by rivals.
“To be focused on Red Bull or Mercedes or Aston Martin, I think it would be a mistake,” said the Frenchman.
“We have to get the best from what we are doing, and to be focused on ourselves. But we made a good step for me between race two and race three.
“And if we're able to bring a couple of updates like this... I think the issue in Melbourne was not the potential of the car, it was more the job that we did as a team to extract the best from this, and that we have to be focused on this.
“Baku will be crucial, because in Baku you have the two qualifyings and the two races and we have to be able as a team to do a better job and to attract the best potential of the car.
“Then the layout of the track in Baku is completely different. But most important is to get the best from what we are doing, and to be focused on ourselves not on the others.”
Vasseur acknowledged that the challenging street venue is not an easy track to get right, but he remains hopeful that recent changes to the SF-23 will pay dividends.
"I will never say what we did on the car and what was the impact on the behaviour of the car,” he said. “But for sure we are looking for something a bit more consistent. And I think that we achieved it.
“I want to have the confirmation in Baku that we're in a different situation. Baku very often is an extreme track, because it's windy, and between the buildings the wind is changing completely direction from corner to corner. And it will be a good exercise for everybody.
“But I think we took the right direction in Melbourne, and we have to confirm it next race."
