Dina Asher-Smith says her "heart does go out" to banned sprint rival Sha'Carri Richardson but is convinced there will be several battles to be had in the coming years.

Richardson, 21, was primed to be one of the favourites for gold at Tokyo 2020 after winning the 100 metres at the U.S. Olympic Track and Field Trials in Eugene, Oregon, with a time of 10.86 seconds.

However, it was revealed Richardson had tested positive for cannabis following that event last month and a consequent one-month ban – starting on June 28 – meant she was ineligible to register for the Olympics, which start on Friday.

Richardson told NBC that her biological mother had died prior to the trials, where she was pictured sharing a warm embrace with her grandmother, who helped raise her.

Asher-Smith, going for gold in the 100 and 200m for Great Britain, has sympathy for the circumstances that led to Richardson's exclusion from the Games.

Speaking to a round-table of journalists at a pre-Games TeamGB call, she said: "I feel sorry for her, her mother passed away, you know? 

"I was kind of thinking about that. Lots of you know my mum, personally I even said to my mum 'if you passed away I wouldn't have done the trials' I have to admit. 

"That's not a criticism, it's just emotionally that's a lot. My mum said 'don't be silly I'd always want you to do it' – it's definitely not a criticism but that's kind of just [how I would be] dealing with that situation. 

"Lots of stuff happened but I'm in absolutely no position to tell someone how to grieve, no one is, that's the first thing that comes to mind she was grieving. 

"If that was my mum…obviously rules are rules but the girl was grieving so your heart does out to her in that whole situation because no one ever wants to lose a parent, so yeah it's awful."

Richardson is the second fastest woman over 100m in the world this season having posted a 10.72s in April. Only Jamaican veteran Shelly-Ann Fraser-Pryce has gone quicker, with a best of 10.63s.

Asher-Smith, the reigning world champion over 200m, has yet to lose a race in 2021 and she is sure there will be plenty of time to face off with Richardson down the line.

"We've both hopefully got very long careers you know?" she said. 

"It's not just about one person as well, you've got so many talented women that can run incredibly fast, it's one of those things I'm like don't worry about it there's so many more chances."

Asher-Smith is regarded as one of Britain's best medal hopes on the track in Tokyo and was described by World Athletics president and two-time Olympic champion Seb Coe as the "poster child" for Tokyo.

While grateful for such compliments, the steely focused 25-year-old is shutting out the external noise as she bids for glory in the Japanese capital.

"I didn't know he'd said that, it's very kind," she said.

"To me, I don't think about those things to be honest. I don't think about things around me, what people are talking about, what the headlines are I just don't think about that.

"I've always been like that because at the end of the day it's me and the track, me and the club, and all this stuff that's going around is literally just noise. 

"The only thing that can affect my performance is the mental state I'm in and physical state I'm in. 

"I try and make sure that is as strong and as good as possible. So, when people talk about all this stuff, postergirl or whatever, cool, I don't know to be honest, I don't pay attention to the noise, the chatter, what the opinions are."

An extremely relaxed Asher-Smith says she has no fear ahead of the Games as she has been preparing her entire career for these moments.

She added: "What's scary about it? I get this question all the time, when I was checking into Heathrow all the BA [British Airways] people were like are you nervous? And I was like 'No what is there to be nervous about?'

"Obviously, this is a very different scale, but I line up and race and I've done that since I was eight years old and I'm very good at it. Obviously, the stakes change, the mechanics change, the precision of it changes but fundamentally this is something I do week in, week out. 

"I love a show, I love a stage, and putting together a performance when it really matters when the lights are on. 

"I love championships, my coach always tell me to quell my excitement through the season until championships and then let it loose. He told me yesterday I can get excited so you can see more energy from me now."