Dunn (0-1) took the loss Monday, giving up three runs on five hits and two walks over 4.2 innings as the Reds fell 5-1 to the Mets. He struck out two.
The former Mariner didn't pitch poorly in his Reds debut, settling down after a first-inning homer by Starling Marte to last 70 pitches (44 strikes), but he got little help from his offense. Dunn began the season on the 60-day IL due to shoulder trouble and posted a rough 6.92 ERA in seven Triple-A starts prior to his promotion, but he'll likely have a long leash on a patchwork Reds staff that still has double-digit arms on the injured list, including Hunter Greene (shoulder).