London (AFP) - Jamaican legend Usain Bolt is determined to bid a golden farewell to his illustrious track career at the World Athletics Championships in London but Canada's Andre de Grasse is eager to gatecrash the party.

The 22-year-old - who signed the most lucrative contract offered to a track and field athlete in 2015 for a reported £7.5 million (S$13.3 million) with an extra £20m in potential bonuses - is looking to improve on his Olympic bronze in the 100m and silver in the 200m last year at the Rio Games.

De Grasse, whose mother took on two jobs to help him pursue his sporting dreams, admits the contract offer put pressure on him, especially as it was with Bolt's kit provider Puma.

"To replace the greatest in Usain Bolt, I knew what I was getting into," De Grasse told Monday's edition of the Daily Mail.

"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," added De Grasse.

With Bolt opting not to run the 200m in London, De Grasse's chance to deny the charismatic Jamaican a 12th world gold medal comes in the 100m, provided he reaches Saturday's final.

De Grasse, who only took up athletics at 17-years-old after trying his hand at basketball, says he needs to beat Bolt before he can be described a rival. "

It's not a rivalry," he told the Daily Mail.

"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."

De Grasse, who has shown some sparkling form this season running a wind-assisted 9.69sec in the 100m at the Stockholm Diamond League meeting, has come a long way since a troubled adolescence and being laughed at when in his first effort at the shorter sprint, he adopted a standing start.

"It was the sideways run-up like in basketball," said De Grasse.

"People in the crowd were laughing. I just looked down and ran."

He has barely looked back since then and off the track, has turned his life around and gained a degree in sociology - he bears a tattoo of the word 'Hope' on his inner forearm.

"I don't believe the world is fair," he said.

"I've seen things all over the world whether it is Doha or in Canada or America.

"I see how people live. You drive through neighbourhoods on your way to events.

"Brazil was like 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."

However, before De Grasse can turn his attention to setting the world right, he has other ambitions on the track.

"I want to be an Olympic champion, world champion, maybe even a world record.

"I'm determined to be the best."