Cleavinger was recalled to serve as the Phillies' 29th man for Tuesday's doubleheader against Boston, Meghan Montemurro of The Athletic reports.
If Cleavinger gets into either game, it will be not only his big-league debut but also his first appearance above the Double-A level. The 26-year-old lefty recorded a 3.66 ERA in 51.2 innings at that level for Reading last season, striking out 36.4 percent of opposing batters but walking 14.9 percent.