They were off the pace in the opening rounds, losing both fixtures to a stacked Auckland side.
They were without star spinner Eden Carson, and veteran opener Suzie Bates picked up an injury and missed the second game.
Both internationals have been ruled out for the back-to-back matches against Northern Districts in Whangarei this weekend.
Carson should be set to go for rounds five and six. She has been resting a troublesome elbow.
But the timeline for Bates’ return is unclear. She has a quad injury.
Coach Gareth Davies said it was a blow, but it was also an opportunity for someone else to step up.
"Any time you take out that amount of caps from a side, it has an impact on you," he said.
"But it’s going to give the other players an opportunity to showcase their skills and demonstrate why they’re a part of our team."
All-rounder Isy Parry replaces Bates in the squad. She is a spinner who is handy with the bat.
The captain, Felicity Robertson, opened the batting in the absence of Bates. But Saffron Wilson is another option at the top of the order.
She has previously scored a century opening the batting for Otago, and she notched 79 in the first game against Auckland at No4.
Whatever the order, someone in the top six will need to post a big score.
The Sparks were rolled for 185 and 172. That was not enough to put Auckland under any scoreboard pressure.
The bowling was not as accurate as it needed to be, either.
"We came up against a strong Auckland side and it showed.
"We’ve got to up our performances, especially with the bat and the ball.
"I thought our fielding was good, it’s just now about someone stepping up in that top five, top six to go and score big runs.
"A big focus of training has been to bowl straighter and fuller, so we can bring the stumps into play more."
Louisa Kotkamp and Emma Black picked up two wickets during the opening weekend. But no-one else was able to snaffle a wicket, such was Auckland’s dominance.
The retirement of Hayley Jensen has taken some oomph out of the attack. The former White Fern operated with some extra zip, and she also had a decent bouncer in her armoury.
Northern Districts had a mixed opening weekend.
They lost the opener to Wellington by eight wickets (DLS method) but bounced back the next day to record a healthy 136-run win.
Lucy Boucher took four for 21 to help dismiss Wellington for a paltry tally of 78.
Jess Watkin missed out with the bat, but the hard-hitting opener shapes as a threat, while Caitlin Gurrey has six list-A centuries and is the heart of the batting lineup.
Hallyburton Johnstone Shield
Whangarei, today and tomorrow
Otago Sparks: Felicity Robertson (captain), Olivia Gain, Caitlin Blakely, Bella James, Polly Inglis, Saffron Wilson, Anna Browning, PJ Watkins, Emma Black, Louisa Kotkamp, Harriett Cuttance, Chloe Deerness, Isy Parry.
