Robert Kubica believes Williams' problems were created by a "bigger group" than just technical director Paddy Lowe.

The former Mercedes boss took a period of absence between the disastrous pre-season and the opening round in Australia and has not been seen from since. 

It is unknown if Lowe will return but team co-founder Patrick Head has since been drafted in as a short-term consultant, taking the Briton's role.

But Kubica's comments hint that Lowe could have indeed left.

"You can have an answer for yourself, but in the end, I don't think it's a one-man issue," he told Autosport.

"Unfortunately, normally the highest person pays the price, but it's the question of bigger groups and bigger people.

"I think the problems which you can see is not only a problem of last month, it's something that was kind of growing [over time]."

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In the meantime, Williams continue to languish at the back of the grid with a car that is still over a second off the rest of the field in qualifying.

Within the team, Kubica has struggled for pace compared to teammate George Russell but he claims any "doubts" over his ability have been cleared.

“I didn’t have doubts, but for sure as I haven’t done any long races in the last eight years so there is always kind of a question mark,” he told RaceFans.

“My physical level is good and I didn’t have problems during the races, which was something probably most of the people were worried about.

“It came out that we shouldn’t be worried about this. I was expecting it.”

That being said, the 2008 Canadian GP winner does admit the main challenge of F1 today is much different to 2010.

“There’s a lot of things which are the same and you get exactly the same feeling or same approach, but there are things which are completely different like managing the tyres,” he explained.

“In general the race pace is completely different compared to the past, especially in our situation where we struggle with the grip.

“The tyres are an extremely important factor and it’s a topic where you have to put a lot of attention.”

2019 is Kubica's first year racing with Pirelli tyres as Bridgestone was the supplier for his final year at Renault.