Blackburn (finger) is slated to throw off a mound Monday after his flat-ground session Thursday went well, the team's official site reports.
Manager Mark Kotsay noted that Blackburn was able to spin some curveballs during the flat-ground session without issue. Consequently, Monday's activity is considered the next step in the natural progression of his recovery. If the right-hander emerges from Monday's session without setbacks, a firmer regular-season debut date could come into focus.