John Lackey threw 40 pitches in the bullpen at Progressive Field yesterday, starting a process the Red Sox hope to will lead to his coming off the disabled list June 5.

Lackey will throw another side session Friday, then four innings in a minor league rehabilitation game Tuesday. A start against the Athletics at Fenway Park would follow.

The righthander has not pitched in a game since May 11 because of a strained elbow.