Triple world champion Niki Lauda says Lewis Hamilton has shown more promise at the start of his career than any other driver he has seen.
Fernando Alonso is pretty much a perfect driver but he's going to have his work cut out keeping Hamilton under control
"To be honest, Lewis has rather stunned me," said Lauda, whose three decades in Formula One have brought him into contact with many of the great drivers.
"I can't remember being so impressed with a young driver in his first season of world championship competition."
Hamilton leads the title chase going into Sunday's Monaco Grand Prix.
The 22-year-old McLaren driver has finished on the podium in each of his four Grands Prix, and heads team-mate Fernando Alonso, the current champion, by two points.
Lauda - who raced against such greats as Ayrton Senna, Alain Prost and Gilles Villeneuve and witnessed Michael Schumacher's career - predicted that Hamilton could win the world title in his debut season.
"It may seem absolutely amazing but, yes, I can see Lewis winning the championship [this season]," he told the Guardian newspaper.
"He is clearly as fast as Alonso, despite the fact that he is completely new. He has a clear mind to face the challenge of F1.
Hamilton has made an incredible impact in just four F1 races
"He genuinely has the chance to win the world championship at the first attempt, assuming of course he can develop the necessary understanding and close relationship with his engineers when it comes to interpreting precisely what he wants from the car.
"If his learning curve continues to climb as it has been doing over the first four races and if the team are capable of improving their car's performance to create an advantage over Ferrari, the title battle will be fought out between Lewis and Alonso."
Lauda, now working as a television commentator, added: "Hamilton has lots of room to move forward. The real danger from him could therefore be next year when he knows all the circuits, but he is certainly the best guy around now."
"For Lewis there is very little pressure at this stage of his career. But Alonso has to work out how he's going to beat not only his team-mate but both the Ferrari drivers as well.
"Fernando is certainly pretty much a perfect driver in my view but he's going to have his work cut out keeping Hamilton under control."
Follow live coverage of the Monaco GP on BBC Radio Five Live and this website. Qualifying is at 1300 BST on Saturday, with the race at the same time on Sunday.