A year ago, the right-hander registered a 3.07 ERA in Triple-A. He followed that effort up this season with a 3.75 ERA in 84 innings.
Boscan landed on the International League disabled list on Tuesday with a left oblique strain, which kept him from being designated for assignment by the Pirates for the second time in the past year.
Pittsburgh previously recalled Moroff on Sunday, and the second baseman appeared in two games and struck out in both of his at-bats.
• Pittsburgh manager Clint Hurdle said catcher Francisco Cervelli went through a three-part test on the field Thursday and continues progressing in his recovery after being hit in the head by an 82.8-mph changeup from Mike Foltynewicz on Tuesday.
"The two parts that I was just a part of watching went very well -- the cardiovascular and defensive agility work," Hurdle said. "He's hitting, and we're just going to give him some more time to recover and see where we are. But I think he's made some good improvements."
• Josh Harrison returned to the Pirates' lineup on Thursday after sitting out the past two games with right leg discomfort. The second baseman last played on Sunday in Milwaukee, when he collided with Brewers outfielder Keon Broxton at first base and exited the game in the sixth inning.
Pat James is a reporter for MLB.com based in Atlanta. This story was not subject to the approval of Major League Baseball or its clubs.