Judge Verstappen and Sainz after 2016 - Key

Toro Rosso technical director James Key says it would be unfair to judge Max Verstappen and Carlos Sainz against each other after just one year in F1.

Verstappen had a hugely impressive rookie season, with the 18-year-old scooping a hat-trick of awards at the FIA Prize Giving Gala at the end of 2015 having secured two fourth places and pulled off a number of breathtaking overtaking manoeuvres. Sainz was also one of the better performers of the season, though his final results were hit by a number of reliability issues which saw him retire from four consecutive races at one stage.

Key says both drivers were on steep learning curves during their debut seasons in F1 and as a result he feels a better comparison will be possible after 2016.

"I suppose they're sensitive to slightly different things, but in a learning year that sometimes changes a bit race by race as the learning process goes on," he told Sky Sports.

"Max certainly in races is pretty aggressive and brave and that has won him a lot of praise and it's been excellent to watch. He's got confidence in himself and the car to go and make some moves that not everyone would risk.

"Carlos has also done a bit of that, maybe less visibly, but he's much more disciplined in the way he goes about things. So he thinks hard about what he's doing, what's coming up, and 'is it right to push now or do I need to wait, bring the tyres in later and really push?' So he's thinking a little bit more and as a result is perhaps slightly less aggressive, but with a longer-term plan in mind in the race.

"In qualy it's been pretty close between them. Max had the recent good form [he qualified ahead in five of the final seven races], but Carlos was top 10 in his first race, which was good and had a bit of bad luck of late. But comparisons will probably be better drawn [in 2016]."

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