Renault admits that it still does not have all the answers it wants on Robert Kubica's potential about making a full-time return to Formula 1.
Although the Polish driver had an impressive test in Hungary before the summer break to stake his claim for a 2018 F1 seat, Renault says there remain some doubts about him.
Speaking in Belgium on Friday, Renault F1 managing director Cyril Abiteboul said that ideally it would like to test Kubica again to get the answers its wants.
However, strict in-season testing restriction mean that there is no chance of running him outside of a race weekend in a current car, which means an FP1 outing would be the only chance.
"We said we wanted to be extremely methodological and analytic about the way that we were approaching things with Robert," explained Abiteboul.
"It was not a PR exercise, it is something that we are taking very seriously and we are trying to leave the emotions on the side.
"We don't have all the answers that we potentially wanted to get from the test, after this test, and in addition to that F1 is very restrictive in terms of tests you can do.
"In a perfect world we would want to do more of this type of test to see if he can race again at the level that he and we could have wanted. It may or may not be possible, we will see."
Abiteboul suggested that one of the factors it needed to understand was whether Kubica could cope with racing scenarios – like changing weather and first corner chaos – that he had not experienced for some time.
"Testing in isolation, a private test, one car, in control of the run, without rain, without first-lap action - all of that needs to be factored into the decision of pursuing or not pursuing," he said.
"I don't want to go further with this. I don't want to create speculation. I don't want to put that the team will have some obligation to go further because there is an interest and willingness to see Robert back. We would all like to see Robert back but it has to make sense."
With regards to timing, Abiteboul said that with other teams sorting out their driver line-ups for next year, his outfit may need to move quick to decide what it does.
"The [driver] market has started to go with the different announcements this week with Ferrari and McLaren, and I expect there will be some other announcements," he said.
"So we will not be sitting back and deciding things ourselves. It has to follow the timing of all the drivers."
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