"It's not a yo-yo [situation] yet," Ambriz said. "It's hopefully just one time. It was so short, so like I never left almost."
Ambriz allowed just one earned run in five innings over four relief appearances with the Redhawks. He only allowed three baserunners in that span.
That was a welcome sign for the Astros after Ambriz's well-documented struggles as summer hit. In his final 6 2/3 innings before the demotion, Ambriz surrendered seven runs and 15 hits, including a three-run, four-hit shellacking against the Rays on July 1 that was the final straw.
Manager Bo Porter and Ambriz both attributed the issues to lack of fastball command, which was the righty's main focus with Oklahoma City.
"I think when he ran into bumps, it had to do with fastball command," Porter said. "The breaking pitches still looked fine. But when you fall behind on that flat pitch, you get into a lot of trouble in this league. He went down there and put the work in to hopefully be a high-leverage guy we need at the back end."
Oberholtzer is again a Redhawk after posting a 7.36 ERA and allowing two home runs in three appearances during his first Major League stint.
Chris Abshire is an associate reporter for MLB.com.
This story was not subject to the approval of Major League Baseball or its clubs.