The Australian bowlers had the England top order in a vice-like grip as the home side went 2-0 down in the series at Derby on Wednesday. The use of Leng, from Yorkshire, and probably the right-handed Charlotte Edwards would help break up Australia's rhythm.
There was also a disturbing lack of urgency among the early England batsmen, a fact underlined by Melissa Reynard's impressive 28 from 44 deliveries later in the innings. She could also find herself thrust into the top order as England attempt to avoid a series defeat. Katharine Winks, a right-arm seam bowler, will make her England debut in place of Lucy Pearson.
Australia are expected to be unchanged for today's 11am start. The fourth of the five-match 50-over series is in Southampton tomorrow.
England: *K Smithies, C Edwards, J Brittin, B Daniels, J Cassar, M Reynard, K Leng, C Connor, C Taylor, S Collyer, K Winks.