Formula 1 drivers have questioned the wisdom of Red Bull's decision to pick teenager Max Verstappen to drive for Toro Rosso next year.
The Dutchman will be 17 when he makes his debut - the youngest F1 driver in history by about a year-and-a-half.
Lewis Hamilton and Jenson Button said they were not ready for F1 at 17, which Felipe Massa said was "a little young".
Many said they were pleased Verstappen had been promoted on the basis of talent rather than financial backing.
But Sauber's Adrian Sutil said the move was a "risk" for Verstappen's career.
|Who is Max Verstappen?|
|He is the son of Jos Verstappen, a Dutch racing driver who competed in over 100 Formula 1 races||This year is his first in Formula 3 and he has won eight out of 27 races|
|Last year he won the World KZ championship - the highest karting category||Verstappen joined the Red Bull junior team earlier this month|
Sutil said: "It's quite a risky move and a surprise for everyone to be announced as F1 driver after only half a season in F3.
"But there are drivers who can manage that, for example Kimi Raikkonen, who did only one season of Formula Renault and performed extremely well.
"But I think you still need a little bit of driving, a couple of years, before you do F1.
"I think 17 is very young but it just shows everything is possible. The downside is if he doesn't perform his career might be ending very quickly."
Button said: "When I was 20, I wasn't ready. I was probably ready at 23, but people are ready at different times.
"Also, if someone comes along and says 'do you want a drive in F1?' you're not going to say no, are you? Because there might not be another opportunity.
"That's what happened to me. Frank [Williams] said to me when I was in the pub with my mates drinking beer and eating sausages and bacon: 'Are you ready for F1?' And I said, 'no'.
"My dad said, 'I can't believe you've just said that. Phone him back and lie to him basically and tell him you are ready.' And then I got the test drive and the race drive. You have to take the opportunity, you have to say you're ready and I hope he is."
|Youngest drivers in Formula 1|
|Jaime Alguersuari (Spain)||2009 Hungarian GP||19 years, 125 days|
|Mike Thackwell (New Zealand)||1980 Canadian GP||19 years, 182 days|
|Ricardo Rodriguez (Mexico)||1961 Italian GP||19 years, 208 days|
|Fernando Alonso (Spain)||2001 Australian GP||19 years, 218 days|
Hamilton said: "I can only say, 'good for him'. I just remember when I was 17, I was calling [McLaren bosses] Martin Whitmarsh and Ron Dennis asking, 'can I go to F1?'.
"And I was very fortunate I had them and my dad keeping my feet on the ground, and helping me making the right steps. And when I got there I was ready.
"I got offered a drive for BMW and I had a chance to race in the last three races of 2006 for McLaren and I know if I had taken an of those opportunities I wouldn't be here. But it's different for everyone - look at Kimi.
"Max has been doing fantastically well, and I wish him all the best and hope he has as good a group of people as I had to guide him through it."
Ferrari's Fernando Alonso, who made his own F1 debut when he was 19 and went on to become the youngest man to win a race and a world championship, said "age is just a number in your passport".
He added: "Before saying anything, we need to see how Verstappen does next year and after six-to-eight races we can see if he was ready or not."