After a lousy first race of the year for Williams, reserve driver Robert Kubica was reluctant to comment on the team's performance or that of its drivers in Melbourne.

The F1 paddock put the rumor mill in motion Sunday evening, suggesting the Grove-based outfit would need sooner or later to promote reserve driver Robert Kubica to a race seat in order to improve the team's state of affairs.

Williams is relying this year on the least experienced driver line-up of its history with 19-year-old Lance Stroll and 22-year-old rookie Sergey Sirotkin.

The Canadian struggled for pace all afternoon on Sunday while the Russian was put out of contention after just a few laps, with an overheating issue.

Frustrated and despondent, Stroll said there was cause for concern at Williams, claiming he could simply not perform at the wheel of his new FW41.

Kubica refrained from adding his two cents on his team mate's negative comments however.

"It would not be entirely correct for me to say what I think, because it's not my role," Kubica told Eleven Sports.

"But I think that Lance Stroll did a pretty good job. It was not easy, because he lost preparation for qualifying and when you lack experience, that is very important.

"That is why Sergey Sirotkin faced such a difficult task," Kubica added.

The Polish driver believes the team performed pretty much according to his expectations, based on Williams' performance in pre-season testing and the lack of development of its new car.

"After Barcelona, I said that to get into Q2 we need to be about two seconds from the leaders. In the end the deficit was about 2.2 seconds," said the 33-year-old.

"What will happen in the future is unknown," Kubica added, "but if we really look at the situation, it was difficult to expect something else at this point."

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