The 24-year-old righty blanked the Dodgers on two hits through four innings, protecting a 1-0 lead, until a few elevated pitches in the fifth and sixth erased his small margin for error. He allowed three runs overall in five-plus innings in the Pirates' eventual 5-3 loss in 11 innings.
"We wanted to give him more of a safety net than just one run," Hurdle said. "But he came out of the chute well. I thought his poise was really good. Looked like he'd been there before."
Significantly, the call on Cumpton will afford another rehab start for Jeanmar Gomez, who had been the prime alternative for the Reds set. Recovering from right forearm inflammation, Gomez went three innings and threw 64 pitches in his first rehab start with Triple-A Indianapolis.
"It didn't make a lot of sense to throw him in Cincinnati if that was the only thing underneath him," Hurdle said. "Jeanmar needs to go out and get another outing under his belt."
That will come on Tuesday, when Gomez will shoot for five innings and 75 pitches for Indianapolis.
Tom Singer is a reporter for MLB.com and writes an MLBlog Change for a Nickel. He can also be found on Twitter @Tom_Singer. This story was not subject to the approval of Major League Baseball or its clubs.