Carlos Sainz Jr joins Max Verstappen at Toro Rosso for F1 2015

The Spaniard, son of two time World Rally champion Carlos Sr, will partner Formula 3 graduate Max Verstappen in an all-F1 rookie line-up at the team next year.

Sainz, who tested with Red Bull this week at Yas Marina, replaces Jean-Eric Vergne, who revealed earlier this week that he would not be staying with Toro Rosso for 2015.

"Ever since I have been part of Red Bull's young driver programme, this has been my aim and I want to thank Red Bull for putting their faith in me," said Sainz.

"I have had a very successful season in World Series by Renault this year and now I am looking forward to taking the step up to Formula 1.

"In the next few months I will be working hard on my preparation, ready to get in the cockpit in Jerez for the first test of next year."

Toro Rosso team principal Franz Tost added: "With Carlos joining Max in our driver line-up next year, we continue the tradition of providing youngsters from the Red Bull programme with their first steps in Formula 1.

"I have watched Carlos progress through the junior categories, always improving as he moved higher up the ladder, culminating in a well-deserved win in this year's World Series.

"However, I also remember the day's testing he did with us at Silverstone in 2013 in the STR8.

"He really surprised me and his engineers that day, with his mature approach and his speed."

Sainz became the first Red Bull junior to win the FR3.5 title, taking a series-record of seven wins in a season.

2015 F1 FIELD SO FAR:

Mercedes: Lewis Hamilton/Nico Rosberg
Red Bull-Renault: Daniel Ricciardo/Daniil Kvyat
Williams-Mercedes: Valtteri Bottas/Felipe Massa
Ferrari: Kimi Raikkonen/Sebastian Vettel
McLaren-Honda: Fernando Alonso (tbc)/Jenson Button or Kevin Magnussen (tbc)
Force India-Mercedes: Nico Hulkenberg/Sergio Perez
Toro Rosso-Renault: Max Verstappen/Carlos Sainz Jr
Lotus-Mercedes: Romain Grosjean/Pastor Maldonado
Sauber-Ferrari: Marcus Ericsson/Felipe Nasr