Nick Heidfeld has been selected to drive in injured Robert Kubica's place this season, according to a German report.
Lotus-sponsored Renault has already announced that German Heidfeld, 33, will be testing at Jerez this weekend, but only as "a potential replacement" for car number 9.
But the German newspaper Bild-Zeitung claims Grand Prix veteran Heidfeld will also be racing in March and beyond.
The newspaper said he has had a seat fitting for the R31 at Enstone.
A Renault source told Bild: "(Vitaly) Petrov is relatively inexperienced. In order to exhaust the full potential of the car, we definitely need a strong and experienced man.
"And the team has already been talking with Heidfeld in the past years," added the source.
Indeed, Heidfeld was a contender for the race seat alongside Kubica this year, as Renault earlier considered ousting Petrov.
But for the moment, Renault is not confirming the news.
A spokesman told DPA news agency that it would be "inappropriate" to take a decision "while Kubica is still in intensive care".
And it is still rumoured that Tonio Liuzzi could be called up for an evaluation for the Barcelona test.
"We must wait for the Jerez tests now, and thankfully the Barcelona ones too," confirmed team owner Gerard Lopez.
Referring to Heidfeld specifically, he added: "We all know that Nick is rather good, but we don't know what level he is in now, we don't know how he does with our car.
"Same goes for Vitantonio Liuzzi, same goes - I don't know - for Bruno Senna, who last year was in a team with a car that could do nothing," said Lopez.
Nico Hulkenberg's manager Willi Weber, however, is convinced: "Nick Heidfeld is going to race," he is quoted by Auto Motor und Sport.