While Valterri Bottas' chances of returning to the grid at Sepang look increasingly likely, Williams may have devised a contingency plan just in case by nominating Pascal Wehrlein as its reserve driver.
Following an internal review by the team of alternatives which included test and development drivers Susie Wolff and Alex Lynn, Williams may decide to settle on Mercedes' young recruit.
As Mercedes AMG's third driver, Wehrlein has endured a fair amount of F1 mileage in 2015, testing for the world championship team as well as for Force India during February's Barcelona testing days.
The German's current level of experience appears better suited by Williams and engine partner Mercedes to race the FW37 at Sepang should Bottas remain unavailable to drive following the painful back injury which sidelined the Finn in Australia. On Thursday, FIA doctors will hopefully green-light Bottas' aptitude to race in Malaysia.
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