Theo Epstein has joined Rob Manfred's office as a consultant.

The former head executive for the Boston Red Sox and Chicago Cubs will consult regarding on-field matters.

"Theo is one of the most accomplished and thoughtful people in our sport," Manfred said in a statement. "I am grateful that he has accepted our invitation to complement our ongoing efforts and provide his insights on making the best game in the world even better for the next generation of fans."