Doubt is something Usain Bolt has had to deal with his whole life and his latest dream to become a professional footballer is no different - but the man himself remains fully focused on turning it into a reality.
Former Republic of Ireland striker and current Perth Glory player Andy Keogh was the latest to question Bolt's ability, describing the trial as 'farcical' for the A-League.
Despite the doubters, Bolt has earned a modest contract offer from the Mariners which the Jamaican is still considering taking.
Though it remains to be seen if he can cut it as a professional footballer, the sprint king isn't letting the haters slow him down and remains determined to inspire.
"They say Bolt wasting his time," Bolt said in an Instagram post.
"They laugh at the dream. They ridicule the hard work. Listen my youths. Every country youth, every ghetto youth, work hard at your dream and let not (a) single soul tell you that (you) can't achieve.
"Remember if you don’t try, you’ve already failed."
As he considers accepting a deal with Central Coast, Bolt has been told to train away from the team, who ended last season with the wooden spoon.
Mariners coach Mike Mulvey has been putting distance between the club and Bolt recently, stressing his focus remains on the players with a contract.
"Last week I asked the club to keep me at arm's length with what was going on," Mulvey said.
"I was briefed when we got back after the game, saying negotiations are ongoing and that's basically the end of it.
"He's not at training, I'm concentrating on the lads that we've got here who are focused on this game on the weekend, which is how it should be."