Tavarez accepted his outright assignment to Triple-A Pawtucket on Tuesday, and he's expected to report there soon.
Because of Tavarez's ability to start and pitch in long and middle relief, his presence gives the Red Sox depth in case someone else goes down with an injury.
There also might be a trade market that develops at some point for Tavarez, as teams are always looking for durable and versatile pitchers.
Tavarez was seldom used out of the Boston bullpen this season, going 0-1 with a 6.39 ERA in nine appearances. The 16-year veteran is 84-71 in his career with 22 saves. Of his 743 career appearances, 108 of them have been starts.
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.