Kubica 'embarrassed' by Williams performance

Robert Kubica said his return to action at a Formula 1 grand prix weekend was difficult work as he took to the Circuit de Catalunya in a Williams car that was "not enjoyable" to drive. Kubica ended Friday as the fastest Williams driver, as they appear to have a difficult weekend in store.

Taking part in is first grand prix session since the 2010 season-ender in Abu Dhabi, Kubica clocked one minute 21.510 seconds in FP1, eight tenths better than team-mate Lance Stroll.

Stroll improved to 1:21.556 in the second practice session, with Sergey Sirotkin, who gave up his car to Kubica in FP1, only managing 1:22.060.

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After driving the FW41 in pre-season testing in Barcelona, Kubica likened the car to a bus and it appears it is yet to significantly improve at the fifth race of the campaign.

"It's difficult to say that it was enjoyable because our car balance was very bad and it was very difficult to drive, so it was difficult to enjoy it," Kubica said.

"But I'm satisfied with the session and how I reacted to difficult conditions and a difficult balance.

"It sounds strange that you can be happy about P19 but actually I'm happy.

"To enjoy it you need to have a car which is suiting your driving style and is giving you margin to drive it.

"Often unfortunately now we are in a position that we are going around the track and we are not driving the car. And this is not enjoyable. This is hard work.

"I know it sounds strange, but it's hard work to be four seconds off the pace, it is harder work that maybe fighting for one tenth or two tenths.

"In our position it's more that you drive the car into what is happening, you don't know what will happen until it happens, and then you react to the car, which is a hard job."