"If they had this thing and it was that cut-and-dry easy for Toronto to pick somebody and the Red Sox were ready to give somebody up, this would have happened already," one source said. "I don't think it's that difficult of a decision."
The source guessed it would take a player or players of "substantial value" for the Jays to allow Farrell to go to a division rival, though the source did not have direct knowledge of the negotiations, which are taking place on multiple levels of each organization.
A baseball official familiar with the discussions told The Associated Press that the Red Sox have asked the Blue Jays for permission to talk with Farrell about the opening in Boston.
The Red Sox have formally interviewed four candidates -- Los Angeles Dodgers third-base coach Tim Wallach, New York Yankees bench coach Tony Pena, San Diego Padres special assistant Brad Ausmus and Baltimore Orioles third-base coach DeMarlo Hale -- to replace Bobby Valentine, but Farrell has been "at the top of their list" from the start, a team source told ESPNBoston.com earlier this month.
The Red Sox were "impressed with all of the candidates interviewed," a team source said, but were particularly captivated by Ausmus, according to multiple baseball sources. However, Farrell remains the top choice because of the current management's comfort level with him, according to a league source.
Farrell served as the Red Sox's pitching coach from 2006 through 2010.
The Red Sox eventually hired Valentine, then fired him the day after finishing their worst season (69-93) in more than four decades.
Major League Baseball prefers that no announcements are made during the World Series, which starts Wednesday. According to a CSNNE.com report, the Red Sox would like to settle on a manager before then.
Information from The Associated Press was used in this report.