Deutsche Fussball Liga (DFL) was initially expected to get the ball rolling on the sale of a 20% stake in a newly-created company handling the Bundesliga's media rights in October.
The business is valued at between 15 and 18 billion euros, with a 20% stake priced at about 3.6 billion euros.
However, the deadline for indicative offers has been delayed to the first quarter of next year, with original plans to complete the process in March now in doubt, one of the sources said, speaking on condition of anonymity.
DFL declined to comment.
The role of DFL boss Donata Hopfen, who committed to a deal after a previous auction last year fell through, is now in question because of the delays, two of the sources said.
A supervisory board meeting will be held on Wednesday to discuss such matters, one source said.
During a DFL member meeting in mid-November, Hopfen announced a working committee to deal with the transaction, which requires at least two-thirds of Bundesliga clubs to sign off on key decision points.
The FIFA World Cup has also been a delaying factor with key DFL executives in Qatar, two of the sources said. Germany lost out on a place in the knockout stages of the tournament last Thursday.
Several private equity funds including CVC, Bain Capital, KKR, EQT, Advent, Blackstone and Bridgepoint came forward earlier this year to express interest in the deal.
DFL, advised by Nomura and Deutsche Bank, had been expected to send out confidential information packages in the autumn, with the first tranche of non-binding offers in December.
The Bundesliga clubs are on an extended winter break until mid-January, after which discussions will resume, one of the sources said.
