"He's thrown up to two innings," said Red Sox manager John Farrell. "He'll remain in extended [spring camp] until [Class A] Lowell opens up, and our plan would be for him to join Lowell to continue his rehab there."
The Spinners begin their season on June 17.
"The velocity hasn't built all the way back yet. We're keeping him on an every-fifth-day work plan," said Farrell. "That's giving him ample recovery time from the outings in which he pitches. That is still planned for the foreseeable future."
Workman has experience from the 2013 pennant race and postseason, which could make him a candidate to help the Red Sox down the stretch this season.
"Extremely valuable," Farrell said of Workman's past experience. "How he throws and how the arm strength returns will indicate how we factor him in and what he's going to be capable of. The fact is, he's back in games, and that's the most important thing at this point."
Ian Browne has covered the Red Sox for MLB.com since 2002. Follow him on Twitter @IanMBrowne and Facebook. This story was not subject to the approval of Major League Baseball or its clubs.