Alongside opener Yastika Bhatia, who contributed 49 runs in 36 balls, the defending champions successfully chased down the target, reaching 191 for three with a ball to spare.
Despite losing wickets before reaching 100 within 13.3 overs, Mumbai faced a challenging task of needing 72 runs off 30 balls.
Harmanpreet, dropped on 40, switched to “beast mode” and took charge of the innings, forming a crucial partnership of 93 runs with Amelia Kerr.

Harmanpreet’s boundary-laden onslaught, especially in the 18th over against off-spinner Sneh Rana, reduced the required runs to a manageable 23 off 12 balls.
Mumbai Indians sealed the win, placing them at the top of the chart with 10 points.
Earlier, Gujarat Giants had posted a competitive total of 190 for seven, driven by dynamic fifties from skipper Beth Mooney (66 runs) and D Hemalatha (74 runs).
The duo’s explosive second-wicket partnership of 121 runs set a strong foundation for Gujarat’s innings, but Mumbai’s successful chase secured their dominance in the Women’s Premier League.
(With PTI inputs)