Renault will sign Nick Heidfeld as Robert Kubica's replacement if the German impresses the team enough in testing at Jerez this weekend.
The grand prix veteran is set to spend a day driving the R31 on either Saturday or Sunday, with Renault reserve driver Bruno Senna driving on the other day.
Team boss Eric Boullier said at Jerez on Thursday that Heidfeld, Vitantonio Liuzzi and Pedro de la Rosa were the leading candidates for the drive. But the other two will only get a chance with the team if it is not satisfied with Heidfeld's performance.
Boullier also categorically ruled out the chances of Kimi Raikkonen or Nico Hulkenberg being given the drive, due to the Finn's rally commitments, and the young German's lack of experience.
"Nick is here to be evaluated," said Boullier. "Once we have finished our assessment of him, if we are happy with Nick, then we keep Nick.
"If we are not, we go to Barcelona and we test some other drivers."
Boullier explained that the team needed an experienced driver to develop the brand new R31 in the early part of the season.
"If this had happened in the middle of the season, then the car would have been developed, and you could give a young driver some miles to educate him in Formula 1," he added.
"But we have to develop this car from scratch, so the obvious choice of driver is an experienced one.
"We need someone to drive the team forwards, but also with the new tires, with KERS and the adjustable rear wing, there are many things going on in the car. So for that you need experience as well."
The team boss said there was still no certainty about when Kubica would be back in action - but is sure he will be out for at least three months.
"He has to go for another surgery tomorrow, for another four hours," Boullier said. "They have to fix the elbow and the shoulder and the wrist. But he is out of danger now and that is the best news we can have.
"I am in more than daily contact with the doctors. He is recovering well. It is going fast actually, because he is a sportsman, so it is much faster than it would be with anyone else.
"He started to feed himself today, and everything is moving. Now is the time for sticking all the bones together and educating the muscles, but we don't know how long that will take.
"All I know for now is that for the next three months for sure he won't be back. After that, it could be four, five six. He needs at least three months to recover physically, and then we see.
"He is already asking questions about the test, so on Monday I will send him a full report that will be read to him. After Barcelona I will go to see him."