The result sees Westminster finish third in the group stage and they will face Shenfield in the first of Saturday's semi-finals
Arran Duguid (25) top-scored for Westminster School as they registered their highest team total (99 for 7) of The Cricketer Schools 100 so far and set up an intriguing contest against Rajasthan Royals Academy.
The batters were backed up by their bowling unit who chipped away at Rajasthan's batting line-up to defend the target and pick up their first win of the tournament.
While none of Westminster's batters went on to register a score of note - Aryan Bagade 16 (21) second to Duguid's 25 - as a collective they kept the scoreboard ticking and mustered something to defend.
Daniel Foulds anchored the chase for Rajasthan with 36 at the top of the order and when the opener fell lbw to Aidan Hincks, the Royals Academy were still well in with a shout at 62 for 4 with 39 balls remaining.
Westminster however continued to turn the screw, drying up runs and taking wickets at regular intervals.
And when Dhruv Gupta claimed two in two, removing Brush and Hurtel-Hymans with consecutive deliveries to leave Rajasthan 74 for 8, suddenly the target of 100 looked a long way off.
Gupta, who had already accounted for the wicket of B Carter earlier in the innings, picked up his fourth, that of Reece Le Mesurier. That was quickly followed by Ayaan Diddee finishing the job, picking up his first of the innings to see Rajasthan bowled out for 78.
Dhruv Gupta finished with terrific figures of 4 for 12, while Jai Gupta recorder 2 for 18, including an outrageous return catch to remove J Carter.
The result sees Westminster finish third in the group stage and they will face Shenfield in the first of Saturday's semi-finals.
Rajasthan prop up the table and will take on Canterbury Academy in the second semi-final.
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