Having sat out the Saudi Arabian Grand Prix to undergo appendicitis surgery, Sainz had a successful return to racing in Melbourne, taking the win with little competition after race leader Max Verstappen was forced to retire due to a brake issue.
Leclerc followed the Spaniard home in second place after qualifying only fifth, two tenths and a half slower than the lead SF-24.
The Monegasque managed to undercut McLaren's Lando Norris for second place but failed to mount a real challenge to Sainz thereafter, subsequently explaining that he "didn't manage the tyres well" in his second stint – the first on hard tyres.
In the 10 laps preceding his second pitstop, Leclerc lost 6.4 seconds to Sainz, whose rubber was seven laps fresher.
Therefore, when asked if there was anything more he could have done to steal the win from his team-mate, Leclerc candidly replied: "Just being better. I think in qualifying yesterday, I haven't been good enough.
"In the second stint today, on the first hard stint, I had quite a bit of graining on the front left after the [virtual] safety car. The last stint was really good, but it wasn't enough. So Carlos has just been better this weekend.
"But it’s been that in the last three years, where we basically will arrive at one race and Carlos will be better and then I'll push and then I'll be better at the next race and then we'll improve like that. And that's very exciting as a driver to have such a fast team-mate."
Sainz is a free agent on the 2025 Formula 1 driver market, with Ferrari having signed seven-time world champion Lewis Hamilton to partner Leclerc from then on.
Hamilton's seat at Mercedes and Sergio Perez's drive at Red Bull will be of interest to the Ferrari man.
While the three-time grand prix winner is not always considered a top driver by the media, Leclerc had a different view when asked why he is underrated: "I think everybody knows Carlos' worth in the paddock. He's one of the highest-rated drivers in the paddock.
"He's been extremely strong every time he was in a Formula 1 car. And he has showed it multiple times. So I don't think he's underrated for that.
"I think everybody knows Carlos' worth. And that's why I've said many times that I'm not too worried about his future, because I'm sure that many, many team principals are… He doesn't say it, but for sure they are speaking with him! And I'm sure he will have many opportunities and he'll just have to make the best choice for his career."
