Jackson was recalled from Triple-A Oklahoma City on Monday, David Vassegh of AM 570 LA Sports reports.
While Justin Bruihl will serve as the opener in Monday's bullpen game against Pittsburgh, Jackson will make his major-league debut as a long reliever. The 25-year-old has made 17 appearances (14 starts) in the minors this year, and he posted a 3.28 ERA and 1.02 WHIP in 71.1 innings.