Ferrari has been Red Bull's closest challenger so far, and Sainz is the only driver other than Max Verstappen to have won this year with his triumph in the Australian Grand Prix.
Red Bull's performance in Japan last weekend, where Verstappen led home a dominant 1-2 ahead of team-mate Sergio Perez, has left few in any doubt that the Milton Keynes-based squad is clear favourite for the titles again this year.
But Sainz has dropped some intriguing hints about what could come from Ferrari as it continues work on some pretty major developments for its SF-24.
And with Verstappen's gap at the head of the drivers' championship having been slashed by his retirement in Melbourne, Sainz has suggested that if Ferrari doesn't lose too much ground to its main competitor in this phase of the year, then that could open up some interesting times later on.
"I think they [Red Bull] are definitely going to have an advantage in the first third of the season until we bring one or two upgrades that makes us fight them more consistently," explained the Spaniard.
"But by that time, maybe it's a bit too late with the advantage that they might have on the championship.
"In the meantime, we need more Australias, but I don't see Red Bull, as a team, making these mistakes very often, no.
"[It's] a shame, because also I missed a race, which for both the team and me, it could be costly in the championship. We're competing in one race less, but at the same time, we're going to give it our best shot. It's my last year in Ferrari also, so yeah, nothing to lose and we will try everything to make it back."
Ferrari boss Fred Vasseur has hailed the progress made with its car in areas of weakness last year – which was high-speed corners and tyre degradation.
And while he is aware of the advantage Red Bull has right now, he reckons that just getting close to the pace-setting team right now is enough to start putting it under pressure and for it to make mistakes, like it happened in Melbourne.
"We made a huge step forward on the high-speed compared to last year and for sure Suzuka is a good example," said Vasseur. "And on the tyre management mode.
"But now we still have weaknesses today. It's always kind of compromise, you improve somewhere and you're losing somewhere else.
"But overall, I think that if you compare with Red Bull over the last four events last year and the first four events this year, we made a decent step forward.
"For sure [we] are still a little bit ahead, but the target is to be able to put them under pressure and with pressure, you are doing more mistakes."
Vasseur is equally realistic about how tight things are behind Red Bull, which is why he is taking nothing for granted over hopes for the rest of the campaign.
"It's so tight that I think what is crucial in my business is the humility," he said. "This [Japan] weekend you had four teams in one tenth in qualifying. It means that you don't have to consider that what you did one weekend will be true the weekend after.
"We will start from scratch next week. And we have to keep this mindset for all the races."
