Chapman made his brief Arizona Fall League debut -- out of the bullpen -- striking out one in a scoreless third inning in Phoenix's 4-1 win over Salt Lake on Monday.
The hard-throwing Cincinnati southpaw easily worked around a leadoff walk to Tim Wheeler (Rockies), popping up Colorado's Nolan Arenado and striking out Ryan Wheeler (D-backs) to end the inning after Tim Wheeler was thrown out at second. He threw eight of his 16 pitches for strikes and reportedly hit 101 mph with his fastball.
Chapman was slated to potentially start for Phoenix on Monday and again Thursday and Oct. 31 as the Reds aim to transition him back to a starter. Either way, he's expected to see very limited action before getting additional work with a Caribbean League club this winter.
"It's preparation before he goes to Winter ball," Reds general manager Walt Jocketty told MLB.com last week. "He's just getting into pitching shape again, throwing bullpens and things like that."
The 23-year-old went 4-1 with a 3.60 ERA in 54 games out of the Cincinnati bullpen in 2011. He struck out 71, but continued to struggle with command at times, walking 41 batters in 50 innings.
Arenado was thrown out trying to stretch an RBI double in the first that plated Adam Eaton (D-backs) for a 1-0 lead. Phoenix responded with two runs in the third when Anthony Gose (Blue Jays) and Corban Joseph (Yankees) scored on fielder's choice grounders. Joseph's two-run double in the sixth off Parker Frazier (Rockies) put the Dogs up by three.
Oakland's Tyson Ross (1-0) picked up the win after allowing one run on three hits over two innings. Evan Crawford (Blue Jays) earned his first save with 1 2/3 perfect frames.
Salt River starter Andrew Oliver (Tigers) walked a pair and allowed one hit over two scoreless frames.
Danny Wild is an editor for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.