The rollicking start by the pair powered India to post an imposing 185 for four wickets after being put in to bat. 15-year-old Verma found gaps comfortably and clobbered the erring West Indies attack to help India reach 50 inside four overs. At the end of six overs, they had raced to 77 for no loss - their best score in the power play.
Although the hosts created opportunities to put brakes on the scoring rate, their fielders - led by Natasha McLean - dropped several catches.
At one point Verma, who was on 41 off 18 balls, seemed to be on the verge of breaking Mandhana's record of the fastest fifty by an Indian (24 balls) in the format, but the right-hander erred on the side of caution to reach her maiden half-century off 30 balls. She thus became the youngest Indian to score a half-century in international cricket. Subsequently, southpaw Mandhana too completed her fifty off 31 balls. The hosts finally got the much-needed breakthrough as Verma (73) gave an easy catch to Kyshona Knight off Shakera Selman.
Stand-in skipper Anisa Mohammed, who led the team in the absence of injured Stafanie Taylor, too, pulled one back and got rid of Mandhana (67) who was caught by Hayley Matthews at long off - after having been dropped as many as four times. Pooja Vastrakar - promoted to try and continue the onslaught - didn't last more than two balls, caught behind off Selman without scoring. Mohammed equalled Selman in picking two wickets as Deepti Sharma was stumped for three. Harmanpreet (21*) and Veda Krishnamurthy (15*) combined to take India to their third-highest total T20I overall and joint-highest T20I total by any side against West Indies.
In reply, West Indies suffered an early hiccup and lost their crucial batter Hayley Matthews (13) who was cleaned up by Shikha Pandey. The second wicket was only around the corner as a running Harmanpreet caught McLean for a two-ball duck off Radha Yadav's first delivery of the match. Shemaine Campbelle and Stacy-Ann King tried to rebuild the innings but a suicidal run by Campbelle (33) led to her dismissal. King ran for a single but a throw at the striker's end by wicket-keeper Taniya Bhatia resulted in an overthrow. Despite the ball being in the hand of fielder, in an attempt to sneak third run Campbelle (33) fell well short.
King struggled in the middle as she could not find any support at the other end. Deepti added to West Indies' misery and got King leg-before for 13. The dismissal of the hosts' last hope led to a collapse and West Indies were restricted on 101 for nine in their 20 overs. For India, Radha, Poonam and Pandey all picked up two wickets each.
Brief scores: India 185/4 (Shafali Verma 73, Smriti Mandhana 67; Anisa Mohammed 2-35) beat West Indies 101/9 (Shemaine Campbelle 33, Radha Yadav 2-10; Shikha Pandey 2-22) by 84 runs. PoTM: Shafali Verma.