Blackburn (foot) appeared in relief for Single-A Stockton against Rancho Cucamonga on Tuesday, allowing three earned runs on two hits and two walks over two-thirds of an inning. He struck out one.
Blackburn was slated to throw about 35 pitches, but he was pulled after just 23 due to his struggles. The right-hander worked himself into trouble immediately upon entering in the third inning, issuing back-to-back walks and allowing a pair of run-scoring singles. Blackburn could still be bumped up to Triple-A Las Vegas for his next rehab appearance Sunday, although it remains to be seen if Tuesday's poor showing alters those plans.