Williams driver Valtteri Bottas has been warned by the FIA he must stop driving the moment he suffers a repeat of the back pain that forced him out of the Australian Grand Prix . Bottas sustained a very small tear in the annular part of a disc in his lower back during qualifying , leading to severe pain . Although the Finn made himself available to drive on Sunday morning ahead of the race , the FIA ultimately declared him unfit . Valtteri Bottas briefs the press about his injury at the Sepang Circuit Medical Centre on Thursday . Bottas declared himself fit for Melbourne after suffering a back injury in qualifying , but still missed the race . Ahead of Sunday 's race in Malaysia , Bottas has now been given the all clear , albeit with the proviso from the FIA that 'in case of a recurrence of pain , or any abnormal feeling , he must stop at the earliest opportunity ' . Bottas has no doubt he will come through unscathed as he said : 'The back is good , no pain , which is nice . 'At the end of last week I could do something without any pain , and during the weekend I could swim , cross-train without any pain , so the recovery was really good . 'We 've done everything we can in this short period of time - luckily there are two weeks - so I feel confident of getting back in the car . ' Bottas has revealed the injury was due to his brake and seat position inside his car , which have since been corrected . 'The back is now in a more neutral position , less pressure on the discs . We are confident that should be it , ' added Bottas . Preparations are ramping up in Kuala Lumpur ahead of the Malaysian Grand Prix . Mercedes director Toto Wolff ( right ) speaks with Bottas in the paddock in Kuala Lumpur . ' I 've never had any problems before with the lower back . That kind of thing normally takes a bit of time to build up . 'But there was no warning , it went suddenly under maximum braking . It was like someone putting a knife in there , with the pain ramping up through to midnight . 'During the night it started to ease off . In the morning I would have been ready to race . ' I did pass the tests , but the FIA had access to all the material from the hospital , from the MRI and that stuff . 'Maybe they thought it was better ( not to race ) in the longer term , which could have been true . 'It was very disappointing , but I also respect the FIA 's decision , with the support great from the team . ' As a precaution , Williams on Thursday announced Adrian Sutil as their reserve driver , with the German back in Formula One after being axed by Sauber at the end of last year . Although Susie Wolff is test driver and young Briton Alex Lynn the development driver , Williams believe experience is crucial should a sudden change be required . Sir Frank Williams said : 'The fight for a top constructors ' championship position will be intense this season . 'Therefore we have selected a driver with recent race experience and are confident if the need arose , he would be a solid pair of hands to race the FW37 and assist our 2015 campaign . '
Williams suffered tear in a disc in his lower back in Melbourne . Injury caused pain 'like a knife ' would , forcing him out of Australian GP . Valtteri Bottas driver insists he is fine to race in Malaysian GP . But he has been warned he must withdraw if he feels more pain .