Carlos Sainz has admitted that he is feeling angry that his career is being stalled at Toro Rosso, but is adamant to keep patient.
Sainz joined the Red Bull junior team in 2015 and has since impressed around the paddock. However, when it came to the demotion of Daniil Kvyat back to Toro Rosso early in 2016, it was Max Verstappen who was pushed up to the senior team.
Sainz was reportedly Renault's number one choice for a seat in 2017 but a move was blocked by Red Bull to keep him in the programme for next season.
"It's difficult," the 22-year-old said.
"Doing a year in formula one like the one I did is very difficult. That's why I'm angry that I am not moving forward."
"We had a very interesting offer from Renault that in the end was rejected by me as much as it was by Red Bull."
"That's life. If I had done that season in any other year I think I would have got a seat at Red Bull, but now the team is full, they are very happy with the two drivers they have."
"As I said, that's life, and sometimes Formula One is difficult to understand. I just have to have patience and it will come," Sainz added.