Erlin also became the first Padres pitcher since A.J. Sager on May 9, 1994, against the Reds to not walk a batter in his first Major League start.
"What Robbie did last night did not surprise me, he's a good pitcher," said manager Bud Black.
Erlin will go back to Tucson, where he will continue as a starting pitcher. His start in the Major Leagues was necessary after the Padres used Saturday's regularly scheduled starter, Clayton Richard, when Friday's game lasted 17 innings. Erlin's deep outing Saturday and the addition of Boxberger should help replenish the Padres' bullpen.
This marks Boxberger's second stint with the Padres this season. He recorded two scoreless relief appearances after being recalled on May 2 and appeared in 24 games last season.
Boxberger took the loss against the Blue Jays Sunday in his first day back. Mark DeRosa tagged him for a solo home run in the 11th before the Blue Jays added two more runs. In his one inning of work, Boxberger allowed five hits and three runs.
Boxberger said he's been working on his mechanics.
"Just getting a consistent motion with my leg kick consistent and keeping everything compact," Boxberger said.
Boxberger is 0-3 with a 5.73 ERA in his 17 relief appearance with Tucson this season.
"He's a guy that has some experience with us, and we like his stuff," Black said. "He's still learning, he's not a finished product, but he's got a Major League arm. We think that he can help us here, but also grow at the same time with experience."
Jamal Collier is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.