Patton, 28, had been suspended for the first 25 games of the season after violating Major League Baseball's Joint Drug Prevention and Treatment Program.
He entered in the sixth inning and ended a Pittsburgh threat on one pitch, though that would be the only out he would record. After the Orioles scored four runs in the bottom of the inning to tie the score at 4, he allowed two hits in the seventh, which eventually led to Pittsburgh scoring the go-ahead run. Nick Markakis' solo home run later in the inning took Patton off the hook.
In 2013, Patton went 2-0 with a 3.70 ERA in 56 games.
This season, Stinson posted a 7.15 ERA in seven relief appearances.
Benjamin Standig is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.