Kimi Raikkonen has insisted that he is "not worried" he might be sharing a grid with Robert Kubica next year.
After a seven-year absence, Pole Kubica looks set to return to Formula 1 next year with Williams.
With only minor modifications to the 2017 car, including a bigger recess in the cockpit side to accommodate the restricted movement of his right arm, the 32-year-old did over 100 test laps in Abu Dhabi on Tuesday.
Also on track was Ferrari driver Raikkonen, who was asked about speculation that some drivers are worried about racing against Kubica next year.
"Why should I be worried?" the Finn responded.
"I'm sure Robert would not be driving if he was not sure of his abilities.
"I am happy for him. It's great if he finds a place at a team again."
However, there have been some grumbles in the paddock about Kubica returning, including one whisper that he basically has to drive the car "one handed".
"That's nonsense," Kubica said in Abu Dhabi. "It's not possible to drive a Formula 1 car with just one arm.
"Certainly I have limitations, but I can compensate with the rest of my body and so far I'm doing quite well."
Kubica insisted that if he is on the Melbourne grid, it will not only be because he has convinced Williams but also himself that he is fully up to the job.
"There are a lot of people wishing to see me back because of the story," he said, "but first I have to ensure that if I get the chance I am ready and prepared.
"If I do come back I am not here to make up the numbers. I have to make sure I can give the best of Robert Kubica."
Kubica represented Sauber and Renault during his first stint in F1 between 2006 and 2010.