Orlando Ramirez-USA TODAY Sports

Theo Epstein is back with the Boston Red Sox.

The three-time World Series champion executive is joining the team's ownership group and will work as a senior advisor, Fenway Sports Group announced Friday.

Epstein, 50, has been working as a consultant with Major League Baseball since January 2021.

"There is no question that Theo left an indelible mark on our history that represented a transformative era," said John Henry, the principal owner of Fenway Sports Group. "Welcoming him as a member of our ownership group and in the role of Senior Advisor to the broader company brings with it a sense of completion. 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. We take great pride in welcoming him to the FSG family and eagerly anticipate the insights and contributions he will bring as we continue to build on the legacy of success he played a pivotal role in helping us shape."

In addition to the Red Sox, Fenway Sports Group owns the NHL's Pittsburgh Penguins, NASCAR's RFK Racing and the Premier League's Liverpool FC.

Epstein will advise FSG owners Henry, Tom Werner, Mike Gordon and Sam Kennedy "on the company's sporting operations across the portfolio and consult on strategic growth and investment initiatives," FSG said in a news release.

"I am thrilled and honored to return to FSG, to join John, Linda (Henry), Tom, Mike, Sam and the ownership group, and to serve in this new role," Epstein said. "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 was the Red Sox general manager from 2003-11, winning two World Series (2004, 2007). He left to become president of baseball operations for the Chicago Cubs (2012-20), winning another World Series championship in 2016.

Boston's 2004 World Series title was its first since 1918 and Chicago's was its first since 1908.

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