The Scuderia endured a dismal Zandvoort outing, with Sainz classifying fifth as team-mate Charles Leclerc retired due to floor damage.
This came after the Monegasque crashed in qualifying, with both drivers complaining that the SF-23 machine was skittish on the limit and they had "zero idea" how it would behave.
Ferrari has promised an all-new car concept for 2024 and is confident the issues are fully understood. Therefore, Sainz says, the team must just perservere with the car for the rest of the term.
He told Sky Sports: “Don’t get me wrong, we have started to understand what it is [with the handling] but there is very little margin to correct it now that the car is built and the car is pretty much done and developed.
“We know we need to change things for next year but for this year, circuits like Zandvoort and windy conditions and high downforce tracks, we are simply going to be slow.”
The Spaniard added that despite the pace deficit (he led the team's Dutch Grand Prix qualifying charge in sixth but was 1.187 seconds adrift of polesitter Max Verstappen), confidence should be taken from how the Ferrari drivers were able to battle with faster cars in a frenetic rain-hit race.
He said: “We were fighting with cars that were a lot quicker than us the whole weekend.
“It was just a whole race of fighting through, getting the calls right… our pace was nowhere near that [to earn fifth place].
“It means we executed the race well; we did everything well.
“I’m happy with the result, not happy with how much I struggled and how difficult it was out there for us.”
Sainz reckoned Ferrari could match its podium finish from Spa as the team contests its home race at low-downforce Monza this weekend.
Anticipating a return to a “normal position”, Sainz said: “For Monza, I expect better things because in Spa, we were a lot quicker than we were [in Zandvoort] and I think honestly, at low-downforce tracks, we should be better and we should be back to our normal position.”
Team boss Fred Vasseur added: “What we can expect is from one weekend to the other, even if [Verstappen] is always at the top of the list, between P2 and P12 is a completely different order.
“At Spa, we were in very good shape. [Zandvoort] was a bit more difficult for us even if the potential was better than the result.
“Each weekend now, we have to start from scratch and nobody can say before who is in front.
“With this kind of convergence of performance, every single detail on the approach - driver management, tyre management and so on - can make a difference bigger than the difference of the package.”
Additional reporting by Kevin Scheuren
