Nuno was 3-2 with a 3.23 ERA in six starts for Reno after missing out in his bid to win a rotation spot this spring. He was 0-7 with a 3.76 ERA in 14 starts for the D-backs last season.
"I did some work, worked on some stuff," Nuno said before Monday's game about his time in the Minors. "I was a starter out there, so was just going every five days. Now, as a long guy, you never know when I'll get in. I've just got to be sharp. Whenever the phone call rings for me, I've got to do my job."
Marshall, meanwhile, had struggled this year after a breakout rookie season in 2014. In 13 games this year he was 0-2 with a 6.08 ERA.
"Actually, the last couple of times, I think he's starting to figure it out," D-backs manager Chip Hale said. "We just needed the length with Nuno, and needed another guy who could throw tonight. It gives [Marshall] some time to go down and just finish off what I think he's started to figure out here."
In other news, left-hander Patrick Corbin pitched in an extended spring game Monday. He threw 3 1/3 innings and allowed two runs on four hits, with a walk and five strikeouts. He threw 54 pitches.
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.