Crossword Genius

Two of Barbirolli's pieces reversed in order? It might have saved someone turning over (7)

Ross

I believe the answer is:

rollbar

'it might have saved someone turning over' is the definition.
(bar which strengthens a car if it overturns)

I cannot understand how the rest of the clue works.

(Other definitions for rollbar that I've seen before include "Sports car safety feature" , "protection for drivers" , "safety feature on vehicle" , "Protection if car overturns" , "Maybe one resisting turnover" .)

I've seen this clue in the Independent.
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