Daniel Ricciardo
Daniel Ricciardo signed a 2-year deal with Renault. In this picture, Ricciardo of Australia and Red Bull Racing walks in the Paddock after practice for the Formula One Grand Prix of Hungary at Hungaroring on July 27, 2018, in Budapest, Hungary. Mark Thompson/Getty Images

Red Bull Racing team principal Christian Horner was reportedly stunned when Daniel Ricciardo called him on Thursday afternoon to inform him about his decision to sign for the Renault works team rather than remain with the Austrian team beyond 2018.

The British team principal is said to have initially thought that his Australian driver was joking before realizing it was real. Ricciardo’s decision to join Renault is said to have caught Red Bull on the wrong foot as they were convinced he will stay on as Max Verstappen’s teammate in 2019.

According to the Daily Mail, Ricciardo had already agreed terms to remain at Red Bull beyond the current campaign after holding talks with team owner Dietrich Mateschitz during the Austrian Grand Prix In July. The team had also agreed to his demands about it being a one-year deal rather than a more long-term commitment.

Moreover, the Australian is said to have pre-recorded a message confirming his commitment to the four-time Constructors’ champions, which was supposed to be released just prior to the Belgian Grand Prix after the ongoing summer break on Aug. 26.

Despite holding positive talks with the Austrian team and even indicating during the British Grand Prix that he is likely to remain with his current employers, he is said to have been looking out for other options that were on the table.

Ricciardo admitted after it was confirmed that he will partner Nico Hulkenburg at Renault in 2019 on Friday that leaving Red Bull was one of the hardest decisions that he has made in his career. He is said to have agreed a two-year deal with the French manufacturer worth £20 million-per-season ($26 million).

“It was probably one of the most difficult decisions to take in my career so far. But I thought that it was time for me to take on a fresh and new challenge,” Ricciardo said on Friday. “I realize that there is a lot ahead in order to allow Renault to reach their target of competing at the highest level but I have been impressed by their progression in only two years, and I know that each time Renault has been in the sport they eventually won."

McLaren, meanwhile, have also confirmed that they came pretty close to signing Ricciardo before he chose to move to Renault. The Woking-based team’s CEO Zak Brown revealed that they are big fans of the Australian and that he had a strong desire to leave Red Bull at the end of this season.

“We had a couple of meetings and we are big fans of Daniel,” Brown told Racer.com. “I think he’s a great guy, I think he’s a great race car driver. How close we came to getting him, I think only Daniel knows the answer to that question.”

“Had we been running more competitively I think that would have increased our odds."

“I think he had a strong desire to leave and I think it was probably pretty close between us and Renault, but ultimately Daniel would be best to tell you how close. But he was certainly someone that we rate very highly and think he’s a great race car driver and a great guy,” he added.

Ricciardo’s departure from Red Bull has now opened the door for Fernando Alonso to land a more competitive race seat in 2019, but it is unclear if the Austrian team see him as an option. Toro Rosso driver Pierre Gasly remains the frontrunner at the moment for the vacancy alongside Verstappen.