The victory turned the tables on the North Islanders after the Sparks lost to the Hinds on Friday and Saturday.
Beth Langston and Leigh Kasperek led the Otago fightback with the bat and ball.
The pair were the major contributors to the Sparks’ total of 238 for nine from 50 after batting first.
The only disappointment the pair offered during their star performances was that both women lost their wickets in the nervous 90s.
Langston and Kasperek combined a match-winning 166-run partnership.
Kasperek had edged her way to 92 runs from 113 balls before she was caught by Hannah Rowe off the bowling of Rosemary Mair.
That left Langston at the crease and she stayed there until the match was in its final over.
She too fell short of making her century when she was bowled by Georgia Atkinson.The Sparks completed their 50 overs with 273 on the board.
Few of the side’s other batsmen made significant contributions apart from opener Morna Nielsen who added a handy 42 at the top of the innings.
Missing out her century could have spurred on Langston who delivered a brilliant performances with the ball.
The Hinds lost wickets at regular intervals as the Otago side ripped through its opponent’s top order.
Langston took three of those wickets for just 22 runs during her 10 overs.
Georgia Clarke also took three wickets and was almost as inexpensive, going for just 27 runs.
Kasperek chimed in with a wicket as her side eventually bowled out the Hinds for 133 in the 40th over.
The 140-run victory turned around the Sparks’ 32-run loss at Oamaru on Saturday. The Sparks restricted the Hinds to an achievable total of 235 runs.
Their effort with the ball was again spearheaded by Kasperek who took a treble of wickets. Her effort was matched by Megan Gibbs who also claimed three Hinds wickets.
The Sparks’ attempt to chase down the total did not start well when openers Megan Gibbs and Caitlin Blakely were both dismissed within seven overs.
Polly Inglis steadied the innings by adding 65 runs though three of her batting partners failed to support her innings.
Once Inglis’ wicket fell Megan Gibbs dug in and got Otago through to 175 for seven by adding 41 runs.
The regular fall of wickets told as the Sparks were eventually all out, 32 runs short of their target. The Sparks will play the Auckland Hearts, Wellington Blaze and the Northern Spirit in consecutive twenty20 games starting on February 8.
• New Zealand will play off for seventh place at the Under-19 World Cup after losing a classification game against South Africa in Christchurch, NZN reports.
The host nation went down by 73 runs at Hagley Oval, one week after beating its African rival by 71 runs in pool play.
South African opener Matthew Breetzke (115) and captain Raynard van Tonder (117) put on 213 for the second wicket as South Africa compiled 284-6.
New Zealand crumbled to 96 for six and only 74 from Dale Phillips added some respectability as it succumbed for 211 in the 44th over.
Its opponent in the final classification game in Queenstown tomorrow will be England or Bangladesh.
The semifinals pit Australia against Afghanistan and India against Pakistan.
