Three people with knowledge of the situation say the San Diego Padres are ready to promote Josh Byrnes to general manager if Jed Hoyer leaves for the Chicago Cubs.
The people spoke on condition of anonymity because no deals have been announced.
Last week, a person familiar with the negotiations told The Associated Press that Epstein has agreed to a contract with the Cubs with a year left on his general manager contract in Boston. The person said compensation must be worked out.
ESPNChicago.com reported Thursday that Epstein will be the Cubs' president of baseball operations and Hoyer the GM.
Byrnes is a former GM of the Arizona Diamondbacks. He and Hoyer both worked under Epstein in Boston.