The Central Coast Mariners' offer to Usain Bolt is "much, much less" than the Olympic great originally wanted, according to A-League chief Greg O'Rourke.

O'Rourke confirmed the Mariners had offered Bolt, 32, a deal after the sprinting superstar went through a trial with the club.

But Bolt will need to accept a smaller offer than he expected to fulfil his footballing dream, with Football Federation Australia (FFA) not funding any part of the deal.

"There's nothing on the table in writing from FFA or funding from the marquee fund as we've said from day one," O'Rourke told SEN on Monday.

"The marquee fund has secured players like [Melbourne Victory attacker] Keisuke Honda and [W-League star] Sam Kerr, people with football pedigree. Bolt has yet to become a professional footballer anywhere in the world.

"Having said that, I understand from Central Coast Mariners that they have tabled an offer to Bolt's management, which he is currently considering.

"That offer is much, much less than what they were originally requesting. If Usain wants to join that club and become a professional footballer, he should follow a journey pretty similar to other trialists, not withstanding for a minute the amount of marketing that somebody like Bolt – the fastest man in the world – can bring to Central Coast and to the broader A-League."

O'Rourke said he felt fans would prefer the governing body in Australia to use its money in other areas.

"There were some marketing conversations about contributions towards attendances, appearances fees if you like," he said.

"In terms of funding him as a footballer, FFA has been consistent that they won't fund him as a footballer.

"It won't change. Football purists would say if you have some money to invest, we don't think you should put it into a trialist like Usain."

The Mariners opened their A-League season with a 1-1 draw against Brisbane Roar on Sunday.