"I didn't quite get that 80 [4.80m, which she missed with her three attempts] which I know I could have got.
"But that's fine because I've got the whole year ahead of me."
McCartney, who leapt to fame with her surprise bronze medal at the Rio Olympics in 2016, was second at one point, then third before Rio gold medallist Ekaterini Stefanidi cleared 4.80m to bump McCartney to fourth.
It was a spectacular event, Russian Anzhelika Sidarova, competing under the neutral flag, clearing all her leaps to boss the event until American Sandi Morris, the Rio silver medallist, took over, clearing 4.95m, to equal her personal best indoors, and which Sidarova could not match. Morris then tried for the world indoor mark, 5.04m, but came up short.
McCartney, 21, is working off a shorter, 12-step runup, but wants to go back to her 14-step routine and is looking to move to bigger poles.
"My technique has come along in the last six months. I know I'm capable of jumping those heights," she said of the rarified territory occupied by the likes of Morris and Stefanidi, who had won her previous 19 major events.
"I don't think it's too far away. But it's sport, things go wrong, they go well.
"But I feel in a good position and in good shape."
The squeals of delight which accompanied McCartney clearing 4.70m and 4.75m point to her elation at how the season has begun.
She's set her sights on the Commonwealth Games, then the Diamond League. Her confidence has been given a jab now that she knows she is able to again foot it with the best.
"It showed I've still got a bit of work to do but I'm heading in the right direction.
"I'm feeling good about it, excited for my first Commonwealth Games," she added.
• World record holder Christian Coleman won the 60m sprint in 6.37s, coming within 0.03s of breaking his own world mark.
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