Carlos Sainz is sure the work done to settle in at Renault over the final four races will help him to hit the ground running in 2018, in what is looking like a crucial year for the Spaniard.

The second generation racing driver admitted becoming increasingly frustrated at the lack of opportunity to progress when he was with Toro Rosso, even speaking of his desire to move on at the home race of Red Bull in Austria.

That earned him a stiff rebuke from bosses but he would ultimately get his wish at the United States Grand Prix after it was agreed he would join Renault for 2018 on loan before making the move early after Jolyon Palmer was dropped.

"I wanted to do a step up after my 2017 season and my step up arrived four races earlier than expected," he was quoted by F1i.com.

"To get to race with the team that I'm going to race in 2018, to get those four races, is obviously a challenge. A lot of effort [went] into that last four races but it has paid off and it will pay off in the future."

Whether his move to the Enstone team will be more than just 25 races likely depends on the future of Daniel Ricciardo, with Sainz the first option to replace the Australian should he decide not to renew his Red Bull contract.

Renault advisor and four-time F1 champion Alain Prost conceded having that uncertainty was something the team had to accept but agreed with the 23-year-old that it was positive to build the relationship early.

"[It's] very important for us," he said. "We are not in the position to be world champions yet. So we have to put step by step.

"We'll see what's going to happen next year with the market, as it's very open. We need to concentrate on the work with Carlos and Nico  [Hulkenberg]."

Related Stories:

• Sainz feels "at home" with Renault after steep learning curve
• Sainz surprised by immediate results with Renault

The late move was part of another strong year for Sainz, with strong results in Monaco and Singapore before justifying Renault's decision to axe Palmer by scoring a seventh place in his first race for the team in Austin

"When there was a chance to score big points we have been the ones scoring big points," he stated. "Whenever the opportunity has presented itself, we've grabbed it.

"Even if on occasions it has been tough to get points in the Toro Rosso or even the Renault, that's why I'm P9 in the championship. That's why I have many points, so I can be proud of where I was."