LONDON (Reuters) - Williams are confident they will be back up to strength with two cars at next week's Japanese Grand Prix, after having only one in Australia last Sunday due to crash damage, but will still have no spare.

Logan Sargeant had to sit out the race in Melbourne after more experienced team mate Alex Albon, the effective number one driver, wrecked his car in practice and was then given the American's due to the lack of a third chassis.