Carlos Sainz has denied that he has had to change his personal image after switching from Toro Rosso to Renault.

When driving for the Red Bull-owned team, the young Spaniard was mainly seen with scruffy hair, stubble and often a backwards-worn cap.

Now that he is a works Renault driver, however, the 23-year-old is clean shaven, without a cap and with a fresh, clean and combed haircut.

Asked if he has been told to adhere to Renault's higher corporate standards, Sainz protested: "No! I shave every Thursday.

"I get my hair cut when I get my hair cut, but because I wear a cap, very few people notice.

"The fact is that negotiations about which cap I will wear - Renault or Red Bull - are still going on. So I think when you wear a cap, you can spend less time in front of the mirror."

Sainz said that a more important issue is the welcome he has got at Renault, including praise from his bosses like F1 legend Alain Prost.

"I know they are happy with the first race so I want to keep this level now," said Sainz.

"Alain Prost is a legend of the sport but also many drivers congratulated me because nobody knows better how hard it is to change teams."

The season continues on Sunday with the Mexican Grand Prix.