Piastri will make his debut for McLaren in 2023, after the Woking-based outfit won a tug-of-war for his services with the Alpine team.
The Australian arrives in Formula 1 as one of the hottest prospects in recent years, having secured the Formula Renault Eurocup, Formula 3 and Formula 2 titles in consecutive seasons.
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The regard in which he’s held has become even clearer in recent days, with Red Bull boss Christian Horner saying he now regrets not signing the 21-year-old to the team’s junior program.
But Piastri faces a huge challenge in 2023, as he goes head-to-head with Norris, who many regard as a future world champion.
The 22-year-old Norris is already in his fourth season of F1, and while he’s yet to win a race, he’s comprehensively overshadowed Daniel Ricciardo in the same car in the last two years.
It’s why Rosberg, the 2016 world champion, says Piastri has his work cut out.
“It is going to be tough for Oscar to do well there,” he told Sky Sports F1.
“Lando is world-class, he’s world championship material there so it’s not going to be easy to go there and do better than Daniel.
“Ricciardo is a multiple race winner, one of the best drivers in the world, and has found it unbelievably tough against Lando. Oscar is brand new to this sport.”
Rosberg added that he felt the gap between Norris and Ricciardo was more to do with the Englishman’s speed, rather than Ricciardo’s struggles.
“All the indications are that Oscar really is one of those future superstars. But I can’t really believe that suddenly Ricciardo has unlearned to drive super fast,” he said.
“Therefore, I think it’s Lando who’s just performing like a world champion at the moment, he’s just driving so incredibly well.
“So I really think it will be a big, big challenge for Oscar next year to be close to Lando.”
Piastri has a two-year deal with McLaren, while Norris has another three years remaining on his contract, reported to be worth in the region of $34 million a year.
“It’s a brave move by Oscar, it really is,” said Rosberg. “It is either he beats Lando or he’s out basically of the sport, so it’s really, really tough, but he believes in himself. And if you think you’re that good, you’ve got to go for it.
“For Oscar, if you’re a young driver and you have the opportunity to race for McLaren, and you’re free to do so, you have to take it. Opportunities like that don’t come around all the time, so he’s done everything right.”
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