Robert Kubica impressed in testing as he continues his recovery from a serious rally crash. Robert Kubica impressed in testing as he continues his recovery from a serious rally crash.

Robert Kubica says it's "too early to say what the next step might be" after posting the fourth fastest time on his return to F1.

The Pole's time of 1:18.572 on Wednesday afternoon was Renault's best of the test and he completed 142 laps - the second highest tally of any driver - on his first run in a 2017 car, six-and-a-half years after suffering career-changing injuries in a rally crash.

Kubica's performance, which displayed both speed and endurance, could open the door to a full-time return to the sport in 2018 but the 32-year-old is unsure what the future will hold.

"After today, it's too early to say what the next step might be," he said. "For now, I owe a big thanks to everyone at Renault Sport Formula One Team for making this test happen."

"I would like more opportunities but the reality is that l don't know. We will have to wait and see," he added.

How quick was Kubica on his first run in a 2017 F1 car?

Kubica's fastest lap was 1.4 seconds off Sebastian Vettel's benchmark and just a tenth off Jolyon Palmer's Hungarian GP qualifying time, although set on the ultrasoft tyre which was not available over the Grand Prix weekend.

On the supersoft tyre, which Palmer used to set his quickest time in qualifying, Kubica's best lap time was around half a second slower - although his fuel level is unknown.

Vettel fastest as Norris and Kubica star on Day Two of Hungary Test

In total, the 32-year-old improved by nearly six seconds over the course of the day, having posted a 1:24.299 on his opening timed lap.

His best lap was also almost two seconds quicker than the time Renault development driver Nicholas Latifi had managed on the opening day of the test at the Hungaroring.

Kubica returns with an innings of substance

Perhaps most significantly, Kubica also demonstrated consistent pace during each of his stints throughout the day as he completed the equivalent of two Hungarian GP distances.

During a long run following the lunch break, Kubica posted 12 laps which were between 1:21.053 and 1:21.654. That matched or bettered the fastest laps set by Palmer (1:21.589) and team-mate Nico Hulkenberg (1:21.611) during Sunday's Hungarian GP.

"It was a fantastic feeling for me to be here today in the RS17 and also it was amazing to see so many fans come to see me out on track, so thank you to all of them," Kubica said.

Picture special: Kubica returns

"It has been an incredible journey to this point, where I have answered many questions to myself. I learnt a lot about the latest generation car, as there are a reasonable amount of differences between it and the Formula 1 cars I have driven in the past.

"The car is certainly wider than before. I was able to work through the team's programme methodically and I think we made good progress. Certainly my understanding of the R.S.17 and the 2017 tyres came on a lot."

Kubica: The comeback story so far

The former BMW and Lotus driver was widely tipped as a future world champion before his one-off participation in an Italian rally between pre-season F1 tests dramatically changed the course of his career.

Just three days after setting the pace at 2011's opening pre-season test, Kubica crashed into a church wall during the Ronde di Andora rally and suffered extensive damage to his right hand, arm and leg. He underwent several hours of surgery and suffered a partial amputation of his forearm.

Why Kubica's worth the wait

With the restricted movement of his arm initially prohibiting him from driving a single-seater again, Kubica made his competitive return in World Rally in 2013 before racing on circuits again last year.

In June, Kubica drove 115 laps in a private test at Valencia in the 2012 E20 car before completing 90 laps at Paul Ricard on the Wednesday before the British GP.

On announcing his participation in the test, Renault confirmed it was in order to determine whether "it would be possible for Robert to return to competition in the upcoming years".

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