Several broadcasters are thought to have an eye on the English Premier League
Television platform BT Vision has stopped selling Setanta Sports after the Irish broadcaster lost its rights to the English Premier league.
Existing customers are still getting Setanta output - either through a package or paid-for service.
But BT Vision said it was reviewing what it would provide "in the event the channel ceases broadcasting".
Setanta is thought to be losing £100m a year, with Deloitte lined up to act as administrator if it fails.
"We are in ongoing dialogue with Setanta and other relevant parties as the situation develops," a BT spokesman said.
Observers said that the company's move was a blow to Setanta, which relies on such platforms to sell its coverage.
The Premier League took rights to 46 of next season's games back from beleaguered firm on Friday after it missed a payment deadline.
Rival broadcasters have been given until Monday to lodge bids for the rights.
The Premier League said it expected to announce the winners of the auction by the end of the week - adding that it would financially be no worse off because of the Setanta problem.
BSkyB and ESPN are favourites to each snap up one package of 23 games, though they may face competition from digital pay-tv service, Top-Up TV.
BSkyB is expected to buy the package of Monday night games - which it has already won from 2010-11 onwards.
"That's the most likely scenario. It would be a neat fit with what they already have, and what they will have from the season after this one," said James Pickles, editor of industry newsletter TV Sports Markets.
SETANTA'S SPORTS DEALS
English Premier League
Scottish Premier League
Blue Square Premier
US PGA Tour golf
Guinness Premiership rugby union (from 2010)
"And it would earn them some more brownie points with the Premier League if they stepped in to help out."
EU legislation means that BSkyB cannot own all the rights, however, and Disney-owned ESPN are favourites to buy the games which take place at Saturday teatime.
ESPN has refused to comment directly on whether it would bid for Premier League rights, but has said it is "interested in rights where they are available and where they make business sense".
The winning bidders could, in theory, sub-licence the rights to another broadcaster, meaning that theoretically Setanta could end up broadcasting Premier League football in the coming season - though analysts say this is unlikely.
There is uncertainty over what will happen to the 23-game deal that Setanta has already won for the three seasons starting in 2010-11.
But analysts expect that if those rights were up for offer again, a tender process would be resolved quickly.
Setanta missed a deadline of Friday to pay the latest chunk of the £30m it owes the English Premier League.
A potential rescue deal from Access Industries, controlled by the US investor Len Blavatnik, fell through. It had proposed buying 51% of Setanta but there had been concerns over how much tax Access could be liable for if it made the acquisition.
The Premier League said it had been working with Setanta "for some time to help them continue as the broadcaster".
Attention will now shift onto Setanta's other contracts - such as those with the FA for England and FA Cup matches, the Scottish Premier League (SPL), and the Blue Square Premier, the top division of English non-league football.
It recently missed a £3m payment due to the SPL - part of a four-year deal worth £54m over four years from 2006 to 2010.
Setanta also owns rights to the PGA golf tour, as well as cricket and rugby union deals.
Setanta is running at an estimated loss of £100m a year, after missing subscriber targets.
The broadcaster has 1.2 million subscribers, 700,000 short of the 1.9 million that industry experts believe they need to break even.