A power steering issue could hamper Kimi R�ikk�nen's Formula One return this weekend as Lotus made a modest impact during Friday's season-opening practice sessions in Melbourne.

With a problem reminiscent of what proved a pain for Jarno Trulli at Lotus' Norfolk-backed rivals Caterham last season, a steering problem first detected by R�ikk�nen during testing in Jerez returned in Australia on Friday.

The 2007 world champion completed just eight laps in morning practice as the Enstone outfit tried to get the Finn the improved precision he is looking for.

And while future updates may help the issue, R�ikk�nen will most likely have to make do with what he has got for the opening qualifying and race of the calendar on Saturday and Sunday respectively.

'It is what it is and I will try to do the best with it,' R�ikk�nen told Autosport. 'It seems to be working OK at some circuits, but in some certain conditions and some places it might give us a small problem, but hopefully before the next race we will have a new one and we can be OK.

'For sure it will take a while before we get it right exactly I think. Here we are fine with what we have now, but at some circuits we definitely have to improve.

'We have many, many different (steering systems) and unfortunately in testing we didn't have time to try all of them. We have to try them all at some point and it is the best time to try them on Friday. It takes quite a while to change it and we knew that it was going to be slippery anyway, and we weren't going to run for a while so we had time. We are going to stick with it for the weekend anyhow.'

Rain also interrupted running in both sessions, with the McLaren's of Jenson Button and Lewis Hamilton looking in the best shape during the drier morning.

Romain Grosjean did at least complete 27 laps over FP1 and FP2 but both drivers admitted there is still work to be done before Saturday's third practice and the soon-to-follow qualifying.

'I had one lap in the morning without traffic and almost one lap in the afternoon so I don't know where we're going to be,' said R�ikk�nen. 'Tomorrow should be a bit better and after qualifying hopefully we are happy.'

Grosjean added: 'We had to be patient, but we managed to get some decent laps in at the end and these were valuable. It's a fantastic track and the changing scenery as you drive through the park is incredible. I feel comfortable and confident in the car and am really looking forward to qualifying.'