Katarina Johnson-Thompson believes her time will come after she fell just short of podium potential at the World Championships in London.

Johnson-Thompson admitted she left another major championship heptathlon wondering what might have been.

At the last World Championships she let a medal slip from her grasp after she inexplicably posted three fouls in the long jump.

This time she will look back on a disappointing high jump - her strongest event - as the reason she ultimately finished fifth.

Denise Lewis, the Olympic heptathlon champion in 2000, warned others are starting to impose themselves.

And nowhere is that clearer than Belgium's Nafi Thiam, two years Johnson-Thompson's junior, who added the world title to her Olympic gold from Rio.

Johnson-Thompson split with coach Mike Holmes last year, ending a nine-year relationship, moving to France to train with Bertrand Valcin's group of talented multi-eventers in Montpellier.

And she insists the change is working and her time will come.

"It always seems to be a case of what might have been with me," she said.

"I know I've got a lot of talent and one of these days things are going to happen for me. It was always going to be difficult bouncing back after that high jump.

"In the past I've maybe been a bit defeatist but I kept working and showed that I've got a proper fighter’s attitude.

"I was really pleased to throw over 40 metres three times in a row [in the javelin] for the first time and that's my best 800m time in four years or so.

"There's lots to work on in the future. My mental attitude has been completely stripped down, everything has changed since I switched coaches, especially the way I approach training and competition.

"I always thought it might take a couple of years to see the effects but this championships was so important being on home soil, it just came a bit too early unfortunately."

And Johnson-Thompson was not alone in looking back on the day with regrets, with British pole vault hope Holly Bradshaw also reflecting on what might have been.

The British record holder failed three attempts at 6.75 metres, meaning she settled for sixth place in a final where, in truth, a medal was at her mercy.

Indeed a repeat of her 6.80m season's best from the City Games in Manchester earlier this year would have been enough for silver, as Greece's Ekaterini Stefanidi, the Olympic champion from last year, proved herself a class above to take gold.

Bradshaw was seventh at the last World Championships and sixth and fifth in her two Olympic appearances in London and Rio.

Like Johnson-Thompson, her podium potential is obvious but she acknowledges her medal collection should be more sizeable than a bronze at the World Indoor Championships five years ago.

"I just feel completely heartbroken to be honest," she admitted.

"I'm in the best physical shape of my life and I simply didn't take advantage of that. Training has been going so well and I felt really confident that I'd be able to do something special in front of this amazing crowd.

"When I look back at this competition and see 6.65m was good enough for bronze I think it will always be a missed opportunity to win a medal on the biggest stage. I'm just totally gutted that I didn't take advantage of it."

Elsewhere, Andrew Pozzi missed qualification for the 110m hurdles final by one hundredth of a second but British team-mate Kyle Langford produced a brilliant semi-final run to make the men's 800m final.

However, the performance of the day - outside of Callum Hawkins impressive fourth in the men's marathon - belonged to Alyson Dixon.

Dixon smiled through every mile as she lead the best marathon runners in the world for nearly two hours.

Dixon was upbeat about her form coming into the women's marathon but admitted she was shocked at how long she held off a top-quality field around a course that took in the capital's postcard landmarks.

Eventually Kenyan runner Rose Chelimo, running for Bahrain, took control of the race to take gold, ahead of two-time world champion Edna Kiplagat and American bronze medallist Amy Cragg.

But 38-year old Dixon won the prize for the most combative performance, with members of her family and club lining the route to add their vocal support.

"I'm lost for words, it was totally amazing. I knew I was in fantastic shape even though it was a very quick turnaround after the London Marathon," she said, after clocking two hours 31.36 minutes to finish 18th.

"I've done mileage like never before, 140 miles a week, and all that hard work has paid off. I never in my wildest dreams expected to be leading for that long."

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