The former Australia captain made a big call to retire one of her key batters which backfired near the end of the Warriorz innings and contributed to their last-ball, seven-wicket defeat to her former side Delhi Capitals in Navi Mumbai on Wednesday.
Lanning flopped to the turf in frustration at the DY Patil Stadium when, with the scores tied, Laura Wolvaardt struck the match-winning boundary coolly through the covers to give Delhi their first win of the campaign.
It meant Lanning's Lucknow-based team, who snapped up the cricketing great in a bid to transform their fortunes, are now the only one of the WPL's five teams yet to win after their third-straight loss.
That was despite Lanning's best efforts as she compiled her first 50 for the Warriorz and her 10th in all in the WPL to equal the record of India skipper Harmanpreet Kaur, who'd notched her 10th for Mumbai Indians just 24 hours earlier.
Afterwards, the focus was on the highly debatable call at the end of the 17th over when, sitting on 3-141, the Warriorz decided to retire Harleen Deol for not scoring quickly enough when she was 47no off 36 balls, and replace her with the big-hitting Chloe Tryon.
Deol, who had started being tied down by Shefali Verma's spin, still looked perplexed by her enforced retirement, as she'd been scoring at a decent rate of 130.
The move quickly backfired once Tryon departed for just one off three balls and the Warriorz accumulated only 13 off those last 18 balls while slumping to 8-154.
"We stand by that decision. It didn't work today -- sometimes it does, sometimes it doesn't -- but there was method behind it," insisted Lanning.
"Tryon is a boundary hitter and we wanted to maximise that as much as we could. Harleen batted extremely well, but it was getting harder and she got a little bit stuck there, as I did.
"We make a decision that's best for the team, and unfortunately for Harleen that's what happened today."
In Delhi's reply, opener Lizelle Lee continued her fine form with 67 off 44 balls, but the visitors made heavy weather of the chase.
They ended up needing six off six balls but a fine over of spin from the wily Sophie Ecclestone left Delhi nerves jangling as Marizanne Kapp had to scuttle through for a leg bye off the penultimate ball just to bring the scores level.
That left the Proteas skipper Wolvaardt to pierce the tight offside ring with a lovely, nerveless drive, taking Delhi to their target on 3-158.
At least, Lanning could enjoy her own form as she went past 1000 WPL runs, only the third batter to do so after England captain Nat Sciver-Brunt and Harmanpreet.
But she's more interested in ensuring Warriorz break their duck on Thursday against the Harmanpreet-led WPL leaders Mumbai.
While Lanning ended up with 54 off 38 balls, her young Australian colleague Phoebe Litchfield also looked really good again with 27 off 20 before she got stumped.
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