The plan is for Lackey to throw another batting practice either in Tampa Bay -- where the Red Sox will travel after their weekend series in Toronto -- or at home when Boston returns to face the Orioles starting Sept. 21.
It will all depend on how Lackey's arm responds, but so far, everything has checked out well.
"He felt good afterward," manager Bobby Valentine said about Lackey's 20-pitch session.
Lackey will get into game action in the instructional league at some point this month, but the amount of work he logs has yet to be determined and he isn't likely to start.
"See a little competitive action. Probably a couple innings," Valentine said.
"I think it will be good for him. That's what his plan has been all summer. It seems like accomplishing something you set out to do would be pretty important for an athlete."
Lackey hasn't pitched a big league game since Sept. 25, 2011. Following that outing, he had Tommy John surgery on his elbow. Over 28 starts with the Red Sox last season, the 33-year-old went 12-12 with a 6.41 ERA, his second year with Boston.