NFL billionaire Robert Kraft still wants to buy a Premier League team despite failing to takeover Liverpool.
The New England Patriots owner was unable to beat Tom Hicks and George Gillett in a bidding war when the Reds went up for sale in 2005.
But Kraft has raised concerns for the laissez-faire way football operates.
He told BBC Sport: "I like to win at whatever I do. But without a salary cap I'm concerned that we might be at a disadvantage.
"We helped found MLS in America. Our league here is starting to really develop, and with our soccer team we've gone to the championship game five times in 21 years.
"I'm just concerned in the Premier League that we might not, with all the different ways of operating, we're not as familiar with all of them.
"Let's say people from all over the world come in and buy teams and maybe they have different reasons for doing it and managing it.
"And you have to compete with that and I'm not sure. But I'm still intrigued."