Western Storm 85 for 2 (Mandhana 52*, Priest 25) in six overs beat Loughborough Lightning 67 for 0 (Devine 46*) in six overs by 18 runs
Smriti Mandhana scored a brilliant unbeaten half-century - and smashed the tournament record for fastest fifty - as Western Storm beat Kia Super League leaders Loughborough Lightning by 18 runs in a match reduced by rain to six-overs-a-side at Taunton.
Taking the aerial route and making the most of short boundaries, the 22-year-old left-hander from Mumbai smashed 52 off 19 balls with four sixes and five fours as Storm posted an imposing 85 for 2.
New Zealand international Sophie Devine top scored with 46, but Storm bowled and fielded with iron discipline to restrict Lightning to 67 for 0 and inflict their first defeat in three outings.
Bidding to extend their five-match winning record in KSL games at the Cooper Associates Ground, Storm lost the toss and were put into bat on a drying pitch beneath leaden skies.
Charged with the task of getting the defending champions off to a good start, the new opening partnership of Mandhana and Rachel Priest accrued nine runs from the first over, sent down by Lynsey Smith.
Off the mark with a straight six, Indian World Cup star Mandhana received a let-off when being dropped at mid-on with her score on seven in the first over.
How Lightning must have regretted their profligacy when Mandhana heaved Sophie Devine over long-on for another maximum in the next over. Typically forthright in her approach, New Zealand international Priest also opened up her shoulders, twice clearing the rope as Devine went for 19 in one over.
Displaying impressive fluency under pressure, the languid Mandhana drove Jenny Gunn to the long-off boundary as runs continued to flow. She then unleashed a startling cover drive for four at the expense of Kirstie Gordon as Storm brought up fifty in the fourth over. Attempting to match her team-mate blow for blow, the feisty Priest lifted Georgia Elwiss high over the mid-wicket boundary, a blow equalled in ferocity when Mandhana registered a massive six over long-on in the same over.
Elwiss exacted revenge when Priest top-edged the final ball of the fifth over to wicketkeeper Amy Jones with the score on 71. England captain Heather Knight played across the line to Smith and departed for a first-ball duck as Storm briefly faltered, but Mandhana kept her foot to the floor, lifting Smith over long-off to realise 50 with her fourth maximum. Determined to get in on the act herself, West Indies international Stafanie Taylor then hoisted the final ball of the innings over deep square leg to stamp Storm's authority.
The Antipodean opening pair of Rachel Haynes and Devine took 11 off the first over, bowled by England World Cup winner Anya Shrubsole, while Freya Davies proved just as difficult to score against as Storm applied pressure.
Appreciating the need to break free, the progressive Devine did rather better against Knight's off spin, helping herself to a brace of sixes to keep Lightning in the hunt.
But Taylor demonstrated clever variation as the fourth over yielded a mere seven runs, leaving the visitors to score 43 from 12 balls. When Davies kept things tight from the other end, Lightning required a notional 30 runs to win off the final over, a task that proved even beyond Devine, who finished four runs short of 50 in an innings that spanned 21 balls and included 3 fours and 4 sixes.