|Kia Super League, Haslegrave|
|Loughborough Lightning 168-6 (20 overs): Van Niekerk 91; Tahuhu 1-9|
|Surrey Stars 134 (19.5 overs): Marsh 41; Devine 2-12, Langston 2-14|
|Loughborough beat Surrey by 34 runs|
Loughborough Lightning, Southern Vipers and Western Storm will contest the inaugural Super League Finals Day.
South African all-rounder Dane van Niekerk struck a tournament-high 91 and took 2-26 to help Lightning beat Surrey Stars by 34 runs.
Meanwhile, Vipers fell to their first loss as Stafanie Taylor's unbeaten 78 led Storm to an eight-wicket win.
Top spot in the table and automatic qualification for the final on 21 August will be decided on Sunday.
Leaders Vipers and Lightning are tied at the summit on eight points and face each other, while Storm - who lie a point behind them - take on Yorkshire Diamonds.
England bowler Katherine Brunt (3-6) took the tournament's first hat-trick as the Diamonds blew away Lancashire Thunder in the Roses match at Old Trafford to secure their first victory of competition.
Yorkshire skittled out the hosts for 71 in 15 overs, with England off-spinner Danielle Hazell also impressing with 4-10, after Alex Blackwell's 59 had helped the Diamonds post 166-6.
Van Niekerk stars as Surrey crumble
In need of a win to keep their chances of reaching Finals Day alive, Surrey's decision to bowl first on a good deck worked against them as Van Niekerk shared half-century stands with captain Georgia Elwiss (22) and Sophie Devine (16).
Van Niekerk's 64-ball innings included 13 fours and three sixes helped the hosts post a tournament-high score of 168-6 in front of a 571-strong crowd at Haslegrave.
The 23-year-old spinner then struck in her first over to have Bryony Smith brilliantly caught behind as the Stars collapsed to 59-6.
Laura Marsh put up a good fight at the end, hitting 41 off 24 balls, but the visitors were bowled out for 134 with one ball of the innings remaining.
Taylor continues to showcase batting prowess
West Indian all-rounder Taylor followed up her match-winning performance against Surrey in Storm's previous match with another batting masterclass to ensure Heather Knight's side would be present on Finals Day.
Former England captain Charlotte Edwards shared a 73-run first-wicket partnership with Suzie Bates, with both players having been dropped, before Knight had her well caught by Anya Shrubsole.
On a tricky pitch at Taunton, Bates hit her first half-century of the tournament, before being trapped lbw by current England skipper Knight as the visitors made 137-3.
Despite a quiet start, Taylor shared 65-run stands with Knight and Fran Wilson and finished unbeaten on 78 off 51 balls as Storm eased home with 13 balls to spare.
Western Storm 140-2 (17.5 overs) beat Southern Vipers 137-3 (20 overs) by eight wickets - scorecard
Yorkshire Diamonds 166-6 (20 overs) beat Lancashire Thunder 71 (15 overs) by 95 runs - scorecard
|Kia Super League|
|Group stage: 30 July-14 August Finals Day: 21 August (Chelmsford)|
|Coverage: BBC Test Match Special commentary on seven group games, plus Finals Day; additional coverage on BBC local radio|