The 6-foot-7 Puk was taken sixth overall by the A's out of Florida in last year's Draft. He was recently promoted to Double-A Midland, and he allowed three runs across seven innings in his debut for the RockHounds on June 19. He struggled in his next start, yielding four runs in just one-third of an inning.
After the 6-1 loss Thursday, Oakland manager Bob Melvin was unsure of Alonso's status for Friday's series opener with the Braves at home.
"We'll see," Melvin said. "Just depends on how these things respond. I knew I wasn't going to be able to use him today, but hopefully he'll respond some and he'll be in the lineup tomorrow. But I'm not sure."
Worth noting • Right-hander Chris Bassitt, back in action on a Minor League rehab assignment with Class A Advanced Stockton on Wednesday night, struck out two batters in one inning, totaling 17 pitches.
"He felt as good as he's felt in a while," Melvin said.
Bassitt, who was shut down from his Tommy John rehab in May because of arm fatigue, will gradually build up innings. It's unclear whether he'll be able to pitch for the A's this season.
Jane Lee has covered the A's for MLB.com since 2010.