Meg Lanning's Delhi Capitals and Alyssa Healy's UP Warriorz tasted defeat on the opening two days of the lucrative league's second edition.
Mooney, whose inaugural spell as the Giants' leader was ruined by injury in her first match last year, was hoping for a kinder launch this time around on Sunday (Monday AEDT).
Instead, the 30-year-old opener-wicketkeeper found the champions, Mumbai Indians, too strong.
Harmanpreet Kaur's side, who'd defeated Lanning's Capitals in the tournament opener, eased to a five-wicket victory over the Giants with 11 balls remaining.
Mooney admitted to feeling a bit of trepidation about her first game back at the helm.Â
Last year's equivalent fixture ended for her following just four balls when she suffered a tournament-ending calf injury.
"I was a bit nervous but got through it unscathed fortunately," she said.
A ğ�— ğ�—”ğ�—«ğ�—œğ�— ğ�—¨ğ�— to finish things off in style! 💥— Women's Premier League (WPL) (@wplt20) Captain @ImHarmanpreet with the winning runs as Mumbai Indians start #TATAWPL 2024 with two wins in a row 🥳Scorecard 💻📱https://t.co/K8TakIEr6g#GGvMI pic.twitter.com/Wlz4R5tnp1February 25, 2024
After losing the toss and being put in, Mooney started in familiar steady fashion as wickets fell around her, including that of rising Aussie star Phoebe Litchfield.Â
The ICC's emerging player of the year was caught for just seven on her debut when mistiming an attempted slog over the top.
Mooney, meanwhile, accumulated 24 off 22 balls before she was caught behind, leaving the Giants floundering at 5-58.
Ash Gardner hit 15 and there was some late-innings defiance from Kathryn Bryce (25no from 24 balls) as the Giants rallied to 9-126, but the Indians were always in control of the chase once captain Harmanpreet took command with her unbeaten 46 guiding them to 5-129.Â
"We let ourselves down in the first 10 overs," Mooney said, praising the efforts of Scotland captain Bryce, who she described as a "a great find".
"She was very good tonight, hopefully this is just a sign of things to come. It is disappointing to lose, but she was one of the positives."
On Monday, one Australian captain is sure to have something to smile about when Lanning's Capitals meet Healy's Warriorz, also in Bengaluru.