"I was saying, 'I'm coming for you, I wanna beat you, I wanna be the greatest, I wanna be the best'.
"It just happened and the world smiled with us. I wanted him to know I'm coming ... don't take it easy on me because I'm coming."
According to De Grasse, he and Bolt will never be "rivals".
The Jamaican eight-time Olympic gold medal-winner has declared his intention to retire following the world championships in London, which start on Friday. De Grasse appears to be the nominated successor.
London will be dominated by Bolt's farewell, but De Grasse will not be mistaking respect for deference. At the recent Diamond League meeting in Monaco, coach Stuart McMillan suggested that Bolt had forced De Grasse out of the 100m race to clear the field for the senior man.
Bolt's management denied the claim fiercely, as has DeGrasse himself.
De Grasse, now 22, won the silver medal in the 200m and bronze in the 100m at Rio. He arrives in London for the world championships in blistering form, having posted a wind-assisted 9.69sec, which doesn't count for official records, in the Stockholm Diamond League last month.
Bolt has publicly endorsed De Grasse, citing similarities between the pair's running styles and stating that the "sport is in good hands" with the youngster breaking through.
Puma, Bolt's long-term sponsor, agree. Within a month of his 21st birthday, the German sportswear company handed De Grasse the largest first contract ever granted to a track and field athlete, reported to be worth a guaranteed $NZ12.23 million, in addition to a potential $NZ35 million in bonuses.
Further lucrative commercial deals have followed from Gatorade and Pricewaterhouse Coopers. De Grasse is not a sprinter in the conventional sense - he is only 1.75m tall and, at 70kg, he is 24kg lighter than Bolt.
"To replace the greatest in Usain Bolt, I knew what I was getting into," De Grasse told Sportsmail. "I did have a bit of hesitation - everyone can be nervous.
"I was thinking, 'Can I handle this and take on the pressure?' I knew it would provide for myself and my family.
"I can't have fears or hold back, I want to relish it."
De Grasse's story also inspires. He grew up playing basketball, dreaming of a career as an NBA superstar.
He did not contemplate track, until a friend hauled him along to a high school regional meet when he was 17.
De Grasse spent his formative years as a disaffected youth in Markham, a multiracial suburb of Toronto. As he drifted through his teenage years, hope began to ebb away.
"Track saved my life," he says. "Life can be difficult.
"I fell into athletics. I remember that first race, I wasn't prepared.
"I wore a T-shirt, baggy basketball shorts and borrowed a pair of spikes. I was very green - I never even knew about starting blocks.
"The first time I ran I made a standing start, the sideways run-up like in basketball.
"People in the crowd were laughing. I just looked down and ran."
De Grasse ran 10.9sec. Tony Sharpe, the former Canadian Olympic sprinter, happened to be in the crowd, scouting a different 400m runner. Startled by De Grasse's time, Sharpe immediately recruited the sprinter.
At last, De Grasse found the purpose he craved. Sharpe has described a battle between "good and evil" pulling De Grasse in different directions.
De Grasse says: "As a teenager, I didn't know what I wanted to do. I lacked guidance and direction. Basketball wasn't working."
He credits mother Beverley with always being there for him.
"She made massive sacrifices for me, paying for basketball camps, working two jobs, dropping me to every practice ... every time, she got me there, no matter what.
"A lot of parents don't do that. She gave me that wisdom.
"My dad ... he's been in and out ... we are OK, but he lives in Barbados."
In early interviews, De Grasse admitted to falling in with the wrong crowd and taking recreational drugs.
"I never really did drugs," he says now, "but I was lost. I find it hard to explain to people what might have happened, if I didn't have sport
"I really don't know where I would have ended up."
He grimaces when asked what became of his old friends.
"I have no idea ... not good, it's hard. I maybe have two or three friends left from high school.
"I had problems in my 10th grade, things weren't going right. Mum took me out of one particular school and changed things for me."
De Grasse has seen through his education, taking a two-month break after Rio to fulfil his sociology degree on scholarship at the University of Southern California.
The word "hope" is tattooed on his inner forearm.
"I don't believe the world is fair. You see it everywhere.
"I've seen things all over the world, whether it's Doha or in Canada or America. I see how people live.
"You drive through neighbourhoods on your way to events. Brazil was striking for that.
'You go past these slum parts and it's not fair. If these kids had the opportunity or met someone to give them the opportunity, things would be different.
"My brother got me into that, because he has a Masters in social work. I've been with him to see kids who have really grown up with nothing.
"I wanted the degree so I can do it properly."
Now De Grasse wants to gatecrash Bolt's grand farewell.
"I was a bit disappointed after Rio, because I felt I could beat Bolt in the 200m. I had a good semifinals and then in the final, maybe the last 20 or 30 metres, I just had very little left in the tank.
"I was relaxed and felt ready, but maybe just six races over six days hit me and I had nothing left.
"It's not a rivalry," he says of the relationship he has on the track with Bolt. "He has dominated for so long - I've still not beaten him, but I'd love to.
"To have a rivalry, you have to have a back and forth. He is on his way out and a veteran ... I'm trying to prove myself.
"I want to be an Olympic champion, world champion, maybe even a world record. I'm determined to be the best."
