Martin (forearm) has thrown two bullpen sessions this week and is close to beginning a medical rehabilitation assignment, T.R. Sullivan of MLB.com reports.
Martin has been out since April 30 with irritation in the right forearm. Prior to the injury, he had emerged as a primary right-handed setup reliever, having posted a 2.70 ERA and 1.20 WHIP before giving up four runs in two-thirds of an inning during the game in which he suffered the injury.