F1 team owner Red Bull looks set to pull the plug on its NASCAR project.
The failure of the project compared with the energy drink company's meteoric success in Formula One is being blamed for the decision.
Reports in the American media early this week say staff at the Red Bull Racing Sprint Cup team are being told the operation will close at the end of the season.
"We are not at liberty to comment on details while negotiations (with investors) are under way," said the team.
NASCAR insiders say North Carolina based Red Bull Racing, headed technically by ex-F1 figure Gunther Steiner, has struggled since its debut in 2007.
A report in the Toronto Sun said it is "well known" that Red Bull mogul Dietrich Mateschitz has been "unhappy" with the NASCAR effort.
"They never really had the level of success (in NASCAR) that I'm sure they were hoping for," said F1 marketing guru Zak Brown, according to USA Today.
They never really had the level of success in NASCAR
"And on the flip side, you have enormous success around Formula One. I'd probably say it's a combination of both, and I'm not sure there was ever the same level of excitement and passion (for NASCAR).
"Dietrich is a winner, and he's not going to go on forever if he doesn't get the results," added Just Marketing's Brown.
He said it is likely Red Bull will chose instead to spend its North American dollars on title sponsoring next year's US Grand Prix in Austin.
"Not that the US GP will ever be the size and magnitude of NASCAR," admitted Brown, "but I'm sure they're not going to just drop the NASCAR team and not fill the void in another sport or with a title sponsorship. The US is too big a market for them."