<text>  Williams driver Valtteri Bottas insists hell be 100 per cent ready to race at this weekends Malaysian Grand Prix, after a back injury forced him to miss the start of the season. The Finn sat out the Formula One curtain-raiser at Melbournes Albert Park in Australia on March 15 after tearing an annular disc in his lower back during qualifying. After such a frustrating Sunday in Australia, I have taken the necessary measures to make sure I arrive in Malaysia fit to race and ready to bring the results home, Bottas said in a statement on Thursday. Williams driver Valtteri Bottas is confident hell be fit to race at this weekends Malaysian Grand Prix . Bottas sat out the Australian Grand Prix after tearing an annular disc in his lower back during qualifying . In order to race at Kuala Lumpur, the 25-year-old will have to pass FIA medical tests at the track on Thursday - something his manager Didier Coton believes will be no problem. Valtteri is in very good shape, Coton told BBC Sport. He is working very hard. I spoke with him today Monday and he is in top shape. He will have to take the FIA medical, which I expect him to pass. I dont see any reason why he wouldnt pass it - he tells me he is back to normal. Im very confident about it, but of course I am not a doctor. Williams currently lie fourth in the constructors championship after Bottas team-mate Felipe Massa secured 12 points with a fourth place finish in Melbourne. Bottas will have to pass FIA medical tests at the Kuala Lumpur track on Thursday in order to race . 