Earlier, Pakistan were all out for 125 runs in forty three overs.
The tearaway quick was quickly in the action as she took the new ball alongside Australian debutant Garth, as Sidra Amin was caught behind for two in the second over.
Garth kept things tight at the other end, her first over was a maiden and her opening spell of five overs leaked just 12 runs.
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That pressure paid off when Muneeba Ali (18 off 41) looked to attack Ashleigh Gardner in the 13th over, only to hole out to Ellyse Perry, who took a skillful running catch.
The introduction of Annabel Sutherland to the attack paid immediate dividends, she trapped Maroof lbw with her second delivery and while the Pakistan captain reviewed the decision, she was unsuccessful, forced to depart for a 46-ball 21.
From 3-60 matters only became worse when the return of Brown saw Omaima Sohail beaten for pace as she chopped on for 13, and in-form batter Nida Dar was cruelly run out at the non-striker’s end when Garth got a fingertip to a straight drive from Sidra Nawaz.
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Pakistan’s final seven wickets fell for just 41 runs as they were bowled out in 43 overs, as Sutherland (2-13) and leg-spinner Alana King (2-25) cleaned up the tail.
Garth went wicketless but impressed with her figures of 0-13 from eight overs.
Once again the only real blemish for Australia was the extras column, with Pakistan gifted 21 extras including 16 wides.
Earlier, Garth was presented with cap No.149 by skipper Lanning as she was brought into the side in place of Megan Schutt, whose workload is being managed with a busy period ahead of the national side.
Pakistan were unchanged from the XI that lost by eight wickets in Monday’s opening match.
Garth, 26, played 34 ODIs for Ireland between 2010 and 2018, before she made the tough call to walk away from her home nation to pursue life as a full-time domestic cricketer in Victoria in 2020.
Garth became eligible to represent Australia last September and her excellent form in both the WNCL and WBBL saw national selectors come calling for December’s tour of India.
Australia and Pakistan will now travel to Sydney ahead of the third and final ODI at North Sydney Oval on Saturday.
