Travis Jankowski, one of the big surprises to make the team, singled in the winning run in the eighth inning in the Reds' 2-1 victory over the Detroit Tigers at Great American Ball Park in the Summer Camp exhibition finale.
Matt Davidson proved the other run with a solo homer.
The Reds are off Thursday then open the season with Tigers on Friday.
The Reds used seven pitchers – all but two of them from the Prasco Park camp – to cover the nine innings. They held the Tigers to the one run on four hits.