BOSTON -- Theo Epstein, who as Red Sox general manager was the architect of two World Series championships, is returning to the organization as a minority owner and part-time senior adviser to its parent company, Fenway Sports Group.

Epstein, who also helped the Chicago Cubs win the 2016 title -- their first in 108 years -- will advise the sports and entertainment conglomerate on operations and investment strategy.

"This is truly a unique opportunity for me -- a chance to partner with people who mean a lot to me; a chance to challenge myself in new arenas; and a chance to use my experience and perspective to help others succeed and win at the highest level," Epstein said in a statement. "The special connection I feel toward this organization and the ownership group has stayed with me through the years."

Fenway Sports Group owns the Red Sox, the Pittsburgh Penguins, Liverpool of the English Premier League and NASCAR's RFK Racing. In his new role, Epstein said, he will be "asking questions, offering opinions, building trust, and supporting the terrific people at FSG to help us reach new heights."

Epstein will be stepping down as a consultant to Major League Baseball, where he worked on rule changes designed to add more excitement to the game. He will remain operating partner for Arctos Partners, a private equity group that has a stake in FSG.

The move is subject to league approval.

After joining the Red Sox in 2002 at the age of 28 -- the youngest general manager in baseball history -- Epstein helped build the ballclub that won it all in 2004, the first Red Sox championship in 86 years. After leaving, he also helped the Cubs end their long title drought.

"There is no question that Theo left an indelible mark on our history that represented a transformative era," Fenway Sports Group principal owner John Henry said in a statement. "With his strategic mind, leadership, and unwavering passion for sports, Theo brings invaluable assets that will drive us forward across our diverse enterprises, especially in our sporting operations across hockey, EPL football, and baseball."