The bottom two teams (17th and 18th) drop automatically, and the 16th-place team plays off against the third-place finisher in the second division. Bielefeld is ahead of Energie Cottbus on goal difference. And three points ahead of last-place Karlsruhe.
After last Sunday's 6-0 loss to Borussia Dortmund, Bielefeld fired Coach Michael Frontzeck.
The 64-year-old Berger, who has been retired for four years, said he would take over for only one game, Saturday's clash with 11th-place Hannover, and would not discuss a longer stay.