Carlos Sainz has ruled himself out of the running to replace Nico Rosberg at Mercedes.
Some pundits, including Martin Brundle, have said that notwithstanding his 2017 Toro Rosso deal, the young Spaniard is the ideal choice.
Team owner Red Bull, however, are not letting him go, and Sainz indicated at an event in Madrid that he has set his sights for 2018 instead.
"Who would not want to be in Mercedes," he said. "Is it a real choice? For 2017 no.
"I have my mind focused on Toro Rosso for 2017 but also to be in a big team in 2018. Most of all I would like it to be Red Bull, but I want to open as many doors as possible."
Sainz openly admits that seeing his Toro Rosso teammate Max Verstappen get the call-up to Red Bull this year was bitter, but at the very same Spanish Grand Prix, he enjoyed his own season highlight.
"It was the best and most complete weekend of the year for me. With the theme that we all know about (Verstappen's promotion), it made me smile inside the helmet, for sure," he said.
Sainz said he is expecting even better in 2017.
"The engine will no longer be a problem," he said, referring to the move to 2017-spec Renault power. "We will win between 15 to 20kph, Toro Rosso has always made a good chassis so we want to look for fifth in the constructors."
Sainz said that he is also looking forward to the new rules and much faster cars.
"It will be like a new category, like climbing from GP2 to Formula 1, so Formula 1 will become 'Formula 1-super' and I think that's what the sport needs."
The 2017 calendar is scheduled to begin with the Australian Grand Prix on March 26.
