The defending champions clinched the berth courtesy of a comfortable six-wicket win against Auckland at Eden Park Outer Oval on Saturday.
But their hopes of extending their 12-game winning streak unravelled late in the return game yesterday.
Auckland posted a challenging total of 258 for eight and held on to win by 24 runs.
Veteran Sparks opener Suzie Bates fractured a bone in her hand while fielding and did not come out to bat.
The captain, Felicity Robertson, stepped up to open in her absence.
Spinner Eden Carson also got a promotion and showed she was capable of much more than her career average of around 11 suggests.
She injected much-needed momentum into the chase, clobbering her second half century in the format.
Her knock of 54 was a career-best and was timely from Otago’s point of view.
The Sparks had slumped to 72 for four.
Carson and Robertson put on 107 before Carson was caught at deep midwicket.
Robertson was joined by Hayley Jensen with 80 runs needed to win and 14 overs remaining.
The game was firmly in the balance.
But Robertson’s fine innings of 80 came to an end when she shuffled to off and tried to whip a delivery from Bree Illing to the fine leg boundary.
Illing mopped up the tail to help dismiss Otago for 234. She finished with four for 49.
Maddy Green top-scored for Auckland with 76, while Carson was the best of the Sparks bowlers with three for 47.
On Saturday, Bates returned to form with an unbeaten 87 to guide Otago to victory.
Polly Inglis (24) and Robertson (23) chipped in some valuable runs in what was a very comfortable chase.
Jensen did most of the hard work with the ball. She took four for 22 to help restrict Auckland to a modest tally of 186 for nine.
And spinner Anna Browning nabbed three for 31 against her old team.
Auckland had been nicely placed at 92 for one. But the wickets of Saachi Shahri for 44 and Maddy Green for 43 ushered in a steady decline.
Hallyburton Johnstone Shield, game played Eden Park Outer Oval, yesterday.—
AUCKLAND
S Shahri c sub (Watkins) b Deerness 41
C Pedersen st Gain b Carson 25
M Green c Robertson b Deerness 76
L Down b Loe 20
I Gaze b Carson 63
B Armstrong run out (James/Gain) 4
P Catton run out (Deerness/Gain) 2
J Penfold not out 10
A Hucker b Carson 0
B Illing not out 2
Extras (2lb, 13w) 15
Total (for 8 wkts, 50 overs) 258
Fall: 1-50, 2-99, 3-143, 4-209, 5-223, 6-228, 7-256, 8-256.
Bowling: E Black 10-2-50-0 (6w), H Jensen 4-0-19-0 (1w), E Carson 10-1-47-3 (1w), M Loe 10-0-56-1, C Deerness 9-0-51-2 (1w), S Bates 3-0-14-0 (1w), F Robertson 4-0-19-0 (2w).
OTAGO
B James c Penfold b Hucker 15
F Robertson b Illing 80
C Blakely c Gaze b Hucker 9
P Inglis c Illing b Jonas 12
O Gain lbw Jonas 7
E Carson c Armstrong b Penfold 54
H Jensen not out 26
E Black b Illing 2
C Deerness b Illing 0
M Loe b Illing 2
Extras (1b, 3lb, 23w) 27
Total (for 9 wkts, 48.2 overs) 234
Fall: 1-24, 2-39, 3-59, 4-72, 5-179, 6-221, 7-227, 8-227, 9-234.
Bowling: B Illing 9.2-0-49-4 (4w), A Hucker 9-0-42-2 (3w), F Jonas 10-1-35-2 (3w), J Penfold 8-0-38-1 (8w), P Catton 3-0-22-0 (3w), B Armstrong 3-0-12-0, M Green
6-0-32-0 (2w).
Result: Auckland won by 24 runs.
