TOKYO — An Instagram memory from six years ago popped up on Melissa Bishop-Nriagu's phone this week, a selfie alongside longtime coach Dennis Fairall moments after she'd raced to a historic silver medal at the 2015 world track and field championships.

Their grins spoke of a much happier time. Fairall was still in the very early days of his battle with a degenerative brain disease. Bishop-Nriagu was healthy and at the top of her game.

On Friday, Bishop-Nriagu, her hamstring bandaged from a recent injury that had her unsure whether she'd even be able to race here, faded to fourth in her 800-metre heat. Then she had to wait -- and hope -- while three more heats went, before learning that her Tokyo Olympics were over.

One of the first text messages she received after learning her fate was from Janet Fairall, her late coach's wife.

"(Janet) has just been so supportive through all of this. And she knew what I was doing, that it was for him," Bishop-Nriagu told The Canadian Press, her voice full of sadness. "(When the selfie appeared) I knew Dennis was watching. He was in my heart around that track today for sure."

Bishop-Nriagu, the national record-holder and one of the finest middle-distance runners in Canadian history, arrived in Japan intent on erasing the heartbreak from her fourth-place finish at the 2016 Rio Olympics. She'd dipped under the two-minute barrier four times this season, her season's best time of one minute 58.36 the quickest she'd run since becoming a mom to daughter Corinne in 2018.

But the 32-year-old from Eganville, Ont., strained her left hamstring a week ago at the Canadian team's camp in Gifu, Japan, and in Friday morning's heat she slowed down in the stretch to finish in 2:02.11 seconds. Her Canadian record is 1:57.01.

"It's been a tough week, I'll be honest," she said. "A few days ago, I didn't know I’d be on the start line.

"Seven days ago, I was in medal shape. I was in Canadian-record shape. And then everything came to a screaming halt," she added. "Sadly, that's what sport is. You’ve got to come to these Games at 100 per cent, and I wasn't 100 per cent. And that’s what's frustrating. And not at all how I pictured my redemption from 2016. It's really hard."

Bishop-Nriagu missed a medal by a heartbreaking 0.13 seconds in Rio. The years since haven't been much kinder. Her comeback from childbirth was difficult. She suffered injuries as she adjusted to her changed body.

Fairall -- her coach of more than 10 years, and a legend in the track world known lovingly as "Big Dawg" -- died on Nov. 6th of progressive supranuclear palsy, a rare degenerative disease. He was 67.

Like other Canadian athletes, Bishop-Nriagu hurdled numerous challenges thrown up by COVID-19. To escape Ontario's pandemic restrictions and cold weather, she travelled to Victoria for a few months over the winter to train. Her husband Osi and Corinne came with her.

The lack of race opportunities at home sent her to the U.S. in search of the Olympic standard, and it paid off.

Her fast times down south pointed to an excellent performance at Tokyo's Olympic Stadium -- until the hamstring injury.

"I ran a total of three times this past week. The team was incredible that I have here. And we did everything we could to get me on that start line," she said. "I think just the stress of dealing with an injury takes a lot out of you. And you don’t recognize it until you’re on that line and vying for a spot."

Bishop-Nriagu led for much of Friday's race. She was fourth heading into the homestretch and had space to move up but looked spent over the final 50 metres.

"I needed to be optimistic. And part of me thought, 'You know what? I can do this, let's be optimistic.' But the truth is, stress takes a lot of you, and that's all I could give today. And it's sad that it's at the Olympics in the heats, because I had much higher expectations."

Bishop-Nriagu will set her sights on next summer's world championships in Eugene, Ore.

"And hopefully COVID is over by then, and we can walk through this world as we used to and not have that outside stress," she said.

She also hopes to clear COVID protocols quickly so she can fly home to her family as soon as possible.

"They're very proud (of me)," she said. "No matter what, they know what I've been through, so they're proud."

Canadians Madeleine Kelly (2:02.39) and Lindsey Butterworth (2:02.45) also didn't move on.

Jamaica's Natoya Goule was the fastest qualifier from the six heats in 1:59.83.

The 800 field is missing a few names from Rio. South Africa's Caster Semenya, who won gold in Rio, and Margaret Wambui, who edged Bishop-Nriagu for bronze there, are banned from competing in the 800 due to high naturally occurring testosterone levels.

Canada will have two runners in the men's 3,000-metre steeplechase final after solid runs in Friday's heats by Matt Hughes and John Gay.

Hughes, from Oshawa, Ont., was fourth in his heat and the seventh-fastest qualifier overall with a season's best 8:13.56. Gay, from Kelowna, B.C., ran 8:16.99, slicing almost four seconds off the personal best he ran at last month's Olympic trials in Montreal to clinch his spot on the Tokyo team.

Lamecha Girma of Ethiopia was the fastest qualifier in 8:09.83.

Django Lovett of Surrey, B.C., cleared 2.28 metres to advance out of the heats in men's high jump, and Crystal Emmanuel ran 11.18 to finish third in her women's 100 heat and automatically move onto the next round.

This report by The Canadian Press was first published July 29, 2021.