Williams could have signed Lewis Hamilton in 2004 but their former engine partners BMW passed up the opportunity, the Formula One team's co-founder Patrick Head said on Friday.
Head told reporters that Hamilton and his father Anthony had visited the team's factory that year after falling out with backers McLaren while the Briton was racing in Formula Three Euroseries.
"They rang up and said 'can we come and see you?'," he recalled. "And they came in and said '(McLaren boss) Ron Dennis has dropped us'.
"We were with BMW at the time and I think Frank (Williams) rang (BMW's then-motorsport director) Mario Theissen and said 'look, this guy looks as if he could be pretty good and whatever and he has come to us saying can we help him,'" continued Head.
"And I think Mario said they weren't prepared to provide any support and we weren't in a position financially where we could finance his racing.
"So much to Frank's annoyance (now), he could have had Lewis in a Williams," said Head, a co-owner of the former champions who now have Toyota engines.
Hamilton, the first black Formula One driver and now one of the hottest properties in the sport, won four races and finished overall runner-up last year in the most sensational debut by a rookie driver.
McLaren announced last month that they had agreed a new five-year deal, keeping the 23-year-old with them to the end of the 2012 season.
Hamilton, who has been backed by McLaren for more than a decade, fell out of contract with that team in 2004 after a disagreement over where he should race the following year.
He had wanted to move up a series, McLaren told him to remain in Formula Three.
"This was not what I wanted...I eventually decided that I was prepared to give up my contract with McLaren rather than stay for another year," the driver recalled in his recent book 'My Story'.
Head said there were no regrets about the missed opportunity.
"There is no point in regretting. We've had various times where we could have had people in there but it's just water under the bridge," he said.
Hamilton lost out by a single point to Ferrari's Kimi Raikkonen last year and Head expected this season to be a re-run of that title duel.
"I think it will be a really serious battle between Kimi Raikkonen and Lewis," he said. "My impression is that Lewis is just a real class act...he is pushing really hard."
Head said he had watched Hamilton at a recent test and been impressed by his commitment and determination to wring everything out of the car.
"I have to say he's got quite a few characteristics, not unexpectedly, quite similar to Michael Schumacher," he said of his compatriot.
"He knows that to beat Kimi Raikkonen he's got to be absolutely at his top level and he's pushing himself as hard as he can do, out of the comfort zone and into the zone where's he really almost just about to fly off the track every lap.
"But then, Michael was like that as well."