The Formula One drivers' merry-go-round is underway with Sebastian Vettel set to exit Ferrari at the end of this season. The Italian team announced on Thursday that Carlos Sainz will replace four-time F1 world champion Vettel for the 2021 season. McLaren have signed up Australian driver Daniel Ricciardo as a replacement for Sainz. Ferrari have identified Spaniard as the ideal support for Charles Leclerc, whose form last season has helped seal the fate of an increasingly frustrated Vettel. Team principal Mattia Binotto said: "We've embarked on a new cycle with the aim of getting back to the top in Formula One. "It will be a long journey, not without its difficulties, especially given the current financial and regulatory situation, which is undergoing a sudden change and will require this challenge to be tackled in a different way to the recent past. "We believe that a driver pairing with the talent and personality of Charles and Carlos, the youngest in the past 50 years of the Scuderia, will be the best possible combination to help us reach the goals we have set ourselves." Sainz said he was "excited about my future" with Ferrari but "looking forward to the season ahead with McLaren". Ricciardo has signed a "multi-year agreement" and will leave Renault at the end of this campaign, yet to start because of the coronavirus, to race alongside Lando Norris next year. "Daniel is a proven race-winner and his experience, commitment and energy will be a valuable addition to McLaren and our mission to return to the front of the field," McLaren team principal Andreas Seidl said. Ricciardo surprisingly left Red Bull, a team with whom he had won seven races in five seasons between 2004 and 2018, to sign a two-year contract with Renault. However, the Australian's first season was fraught with difficulty and he failed to make a podium. It seems he has now decided McLaren, who will switch to Mercedes engines in 2021, are the better bet for his long-term prospects. "With Daniel and Lando as teammates, I believe we have two racers who will continue to excite our fans and help the team grow," Seidl said. McLaren chief executive Zak Brown said: "Signing Daniel is another step forward in our long-term plan and will bring an exciting new dimension to the team, alongside Lando. This is good news for our team, partners and of course our fans." Renault issued a short statement saying discussions with Ricciardo over a renewal of his contract had not been successful. They gave no indication of who might replace the popular Australian, although their have been reports that double world champion Fernando Alonso could make a comeback with the team that took him to his titles in 2005 and 2006. The 38-year-old Spaniard last drove for McLaren in Formula One in 2018. Sainz achieved a career-best third place finish in last season's penultimate race in Brazil and is the front-runner to drive next year for Ferrari, who announced earlier this week that Vettel is to depart the Scuderia at the end of the 2020 season. Brown said of the Spaniard: "I want to pay tribute to Carlos for the excellent job he has been doing for McLaren in helping our performance recovery plan. "He is a real team player and we wish him well for his future beyond McLaren."