CHICAGO — Boston Red Sox executive Theo Epstein has agreed to a five-year contract with the Chicago Cubs, according to multiple media reports.

The 37-year-old Epstein would leave the Red Sox with a year remaining on his contract as general manager and take over what is expected to be an expanded role with the Cubs, who have gone 103 years without a World Series championship.

Radio station WEEI in Boston, ESPN the Magazine and SI.com all cited unidentified sources in reporting that Epstein has agreed to a deal. Details, which could include compensation to the Red Sox, were still being worked out.

The Cubs declined comment Wednesday and Red Sox officials could not be reached by The Associated Press. On Tuesday, a person familiar with the situation told the AP that Epstein was likely to join the Cubs within 48 hours.

With Epstein at the helm, the Red Sox ended an 86-year World Series championship drought in 2004 and won the title again in 2007.

Cubs chairman Tom Ricketts fired GM Jim Hendry in July.

Peter Abraham of the Boston Globe reported that two team sources confirmed that Epstein reached a deal with the Cubs and would leave the Red Sox by the end of the week.

Abraham reported that assistant general manager Ben Cherington is expected to take over for Epstein in Boston. The report said that Cherington has been acting as the “de facto general manager for several weeks.”

Cherington, 37, is a New Hampshire native and has been with the Red Sox since 1999. He was part of a team that filled in for Epstein when he briefly left the organization in 2005 and early 2006.

Sports Illustrated’s Jon Heyman reported that Epstein would become the head of baseball operations with the Cubs.

He takes over a team that has not won a World Series since 1908. The Cubs went 71-91 in 2011, finishing fifth in the NL Central, ahead of only Houston.

Boston has missed the playoffs the last two seasons, suffering the biggest September collapse in baseball history by going 7-20.

His expected departure would be the latest in the wake of Boston’s disastrous finish. On Sept. 30, two days after the Red Sox were eliminated from playoff contention on the final day of the regular season, Terry Francona’s eight-year stint as manager ended.

Through Sept. 3, the Red Sox held a nine-game lead over the Tampa Bay Rays for the AL wild card. The teams were tied in the standings going into the final day of the regular season. The Red Sox lost to Baltimore 4-3 a few minutes before the Rays beat the New York Yankees 8-7 in 12 innings to gain the playoff spot.

It was a startling fall for the Red Sox and Epstein, who attended Brookline High School close to Fenway Park, and became baseball’s youngest general manager ever at 28 years, 11 months when he was appointed on Nov. 25, 2002.

But he’s been criticized for giving long-term, costly contracts to free agents J.D. Drew, John Lackey and Carl Crawford, none of whom came close to meeting expectations.

Hendry also was criticized for giving similar deals to pitcher Carlos Zambrano, left fielder Alfonso Soriano and right fielder Kosuke Fukudome, who was traded last season.

One of Epstein’s highest priorities could be determining the future of manager Mike Quade, who has one year left on his two-year contract.

Oneri Fleita, the Cubs’ player personnel director under Hendry, and director of scouting Tim Wilken already have been retained by owner Tom Ricketts.

Also to be determined is the future of the emotional Zambrano. He cleaned out his locker and talked about retiring after giving up five homers and being ejected during a loss to Atlanta on Aug. 12. He was suspended for 30 days without pay and then it was decided he would sit out the rest of the season one year after undergoing counseling following an outburst in the dugout against teammates.

Zambrano was 9-7 with a 4.82 ERA and has a year left on the five-year, $91.5 million deal he signed in 2007.

Ricketts has been impressed with the Red Sox model and how they overhauled Fenway Park and increased revenue streams by adding seats above the Green Monster in left field and other parts of the stadium. Fenway is the only park in the majors older than Wrigley Field.

Ricketts said he was seeking a general manager who could use the new statistical and analytical data in baseball in conjunction with traditional scouting, a description that fits Epstein.