The defender stated that the Brazilian wonderkid has the potential to reach the level of club legends such as Eden Hazard and Arjen Robben.
Estevao burst onto the scene at Palmeiras, quickly attracting attention from Europe’s top clubs. Chelsea eventually won the race for his signature in a deal that could rise to £50 million ($67m).
After turning 18 and facing Chelsea in the FIFA Club World Cup, he completed his move to west London in the summer of 2025.
Cahill believes the winger’s talent and mentality make him one to watch for the future.
“I've been at the Bridge a few times this season and the fans can't get enough of him,” he told Goal.
“He's one of those players where you can see the fans on the edge of their seat when he picks the ball up, which is what fans pay the money for, to come and see. In my day it was the likes of Hazard and Pedro, there's Willian, and the list goes on.
“It's those players that you're looking for to unlock situations, to create something out of the blue. You're waiting in these big moments, aren't you, for someone to unlock, someone to create something. He's somebody who can certainly produce that.
“And you look at his age, you'd imagine he's only going to get better and better. So it's exciting for the Chelsea fans. It's just a shame that he's taken a bit of an injury, but that’s part and parcel of the game. He is certainly a huge talent.”