RB Leipzig are likely to miss out on European football next season - despite finishing second in the Bundesliga.
RB Leipzig and Red Bull Salzburg, who won the Austrian Bundesliga title on Saturday, are both owned by the energy drinks company Red Bull.
UEFA rules prohibit clubs with strong links to one another from playing in their competitions in the same season.
The UEFA administration, headed by UEFA general secretary Theodore Theodoridis, will make a final decision next month on whether the two clubs can play in next season's Champions League.
If they rule only one Red Bull club can play, Salzburg will get the nod because they finished higher in their league.
It would also mean Leipzig would be barred from playing in the Europa League as there is a chance Salzburg could drop into UEFA's secondary competition at the end of the group stages.
A UEFA spokesman said: "All criteria, including matters of ownership will be verified for each club by UEFA only once we have received the competition entry forms and documentation from the national football associations and clubs following the end of the season in the respective leagues."