Blackburn (forearm) is scheduled to throw a bullpen session Sunday, Susan Slusser of the San Francisco Chronicle reports.
Blackburn continues to progress in his recovery from the right forearm strain sustained in mid-March, and the bullpen session was expected after he advanced to throwing from 90 feet last week. The 24-year-old is eligible to come off the 60-day disabled list at the end of May, and a return around that time still appears possible.