Can Katarina Johnson-Thompson banish her Olympic bogeyman? After a supremely relaxed ­performance on the first day of the women’s ­heptathlon he should be quaking in his boots.

Johnson-Thompson defied her injury-hit buildup to these Games to knockout season-bests in the high jump and 100m hurdles and a huge personal best in the shot put to place herself in pole position at the end of day one of the seven-discipline event.

“It was a good day, a very good day, one of the best I’ve had in a long time,” she said.

“There were a couple of really good signs and a good couple of events. I’m really, really pleased with it.”

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With three events – the long jump, javelin and 800m – to come on Friday Johnson-Thompson has an overnight lead of 48 points, with her long-time rival Nafissatou Thiam of Belgium in second with 4,007 and the younger American challenger Anna Hall in third with  3,956.

Throughout the day, Johnson-Thompson was shoulder to shoulder with Thiam, who she has competed against since junior competition, the two taking it in turn to lead the field.

As the evening session started Johnson-Thompson was in front by 24pts, when the athletes came out on to the field for the shot put, one of her weaker events and one of Thiam’s strongest.

For an athlete who threw 13.64 metres when she won the world title last year, Johnson-Thompson’s first throw of 13.38 was a ­disappointment, 12.65 on her second provoked a ­grimace.

Showing a strength of ­character that has had ample opportunity to grow throughout her career, she threw 14.44, a whopping half a metre further than her ­personal best, a whoop of delight and a leap into the air revealing how much it meant.

Always the favourite in this ­discipline, Thiam missed her first throw, but her second was a season-best of 15.20, which she promptly beat with her third throw of 15.54. Hall topped out at 14.11.

After three events, Thiam edged ahead with 3,070, but Johnson-Thompson’s barnstorming shot put meant the lead was narrowed to 50 points, with the Liverpudlian on 3,020 and Hall on 2,965 in third.

Then it was time for the final event of the day, the 200m. Thiam managed 24.46sec in her heat, meaning ­Johnson-Thompson needed 23.92 to go into first. She managed 23.45, ­giving her 1,035pts. She fell panting to her knees.

It had been a long day and Johnson-Thompson put on a confident and relaxed performance that almost looked as though she was enjoying herself.

She had come out of the blocks, pulling out a season’s-best of 13.40sec in the first event, the 100m hurdles. Then it was time for another season’s best thanks to a monster high jump of 1.92 metres. After the morning session’s two events she was in first place, racking up 2,197pts, while Thiam was second on 2,173 with Hall’s season’s-best jump of 1.89 putting the 23-year-old up to third place with 2,164.

The pressure on Johnson-­Thompson in the leadup to these Games has been immense, with hopes that she could, at last, achieve the Olympic dream that has evaded her.

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She has two world titles, two ­Commonwealth titles and a ­European ­silver, but has not been able to reach her potential in Olympics, finishing 14th at her debut Games in 2012, ­coming sixth in 2016 and failing to finish in 2020 because of injury.

A year ago, her hopes of ­redemption seemed strengthened, when she became world champion again in Budapest, joyously seeing off a challenge from Hall.

After years of struggling with her fitness, she said the world title had given her some measure of peace. “I am worth a medal if I’m in one piece,” she said then.

But injury hit again and she was forced to pull out of the European championships at the start of June after three events. .

On Thursday she said she had been feeling in strong form in the leadup to the Games. “It’s been going really well. I had no injuries since Rome,” she said.

“You never really know what to expect when you don’t compete as much.

“But I’m really happy I was able to put out what I’ve been seeing in training.”