Sainz's Ferrari contract won't be renewed after this season, with the Scuderia making a spectacular move for long-time Mercedes star Lewis Hamilton instead.
The news initially left Sainz in a tricky position, with perhaps the vacant and hotly contested seat at Mercedes his only realistic avenue of remaining in a top team.
However, his Australian Grand Prix win just two weeks after surgery for appendicitis has underlined his credentials and dedication to his craft, and following the race he received a boost by Red Bull team principal Christian Horner voluntarily throwing Sainz in the mix as a contender for Sergio Perez's seat.
Ferrari hiring Sainz as Sebastian Vettel's replacement in 2021 was seen by some as a conservative choice at the time, but following his performances alongside Charles Leclerc, the Spaniard's stock is perhaps as high as it has ever been.
According to Norris, his former team-mate at McLaren, it would be "silly" for people to still underestimate Sainz.
"You're silly if you underrate him," he said in the Australian Grand Prix post-race press conference. "People know what he's capable of doing, know his effort level, his approach and dedication to wanting to be one of the best, exactly like he's proved today, and over the last couple of weeks.
"I'm sure you have plenty of drivers who probably wouldn't have tried as hard and dedicated so much of their time and effort to trying to recover. For the people who know what he's capable of doing, you would never ever say he's underrated."
Leclerc said team principals in the F1 paddock are acutely aware of the value Sainz would bring, meaning he is not worried about where his current team-mate will end up.
"I think everybody knows Carlos' worth in the paddock, he's one of the highest-rated drivers in the paddock," Leclerc added after being outperformed by Sainz in Melbourne.
"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.
"I'm not too worried about his future, because I'm sure that many team principals are… he doesn't say it, but for sure they are speaking with him!
"I'm sure he will have many opportunities and he'll just have to make the best choice for his career."
Replying to the comments from Leclerc and Norris, Sainz said: "There are some kind words there, but I agree with them.
"People that maybe don't have an insight and don't know as much about this sport, if they want to underrate me, I'm fine with that.
"I don't care honestly, but I care about the people that know the sport, that have seen my data, seen how I work, seen my speed. That's the thing I care about, and I don't feel underrated by them."
