Along with Mark Gubicza and Bret Saberhagen, Jackson rounded out a cast of talented pitchers developed by the Royals in the early 1980s. After some early successes, Jackson fought through an 18-loss season in 1987, and the Royals, desperate for a shortstop, dealt him to the Reds for Kurt Stillwell.
In 1988 Jackson dominated NL hitters with a moving fastball and wicked slider on his way to a league-leading 23 victories. He finished second in the Cy Young Award balloting only because of Orel Hershiser‘s record-setting scoreless innings streak. Injuries limited him to a 6-11, 5.60 record in only 20 starts in 1989, and after another middling season in 1990 he signed with the Cubs as a free agent.
In just seventeen appearances in ’91, Jackson issued more walks than strikeouts. A similarly disappointing start the following year earned him a mid-season ticket to Pittsburgh in a deal for infielder Steve Beuchele, but after the Pirates’ pennant drive he was left unprotected in the expansion draft.
Jackson was selected by the Florida Marlins with their twenty-seventh pick, but soon after was traded to Philadelphia for pitching prospects Joel Adamson and Matt Whisenant. With the Phillies, Jackson enjoyed a brief resurgence, winning 12 in 1993 and earning his second All-Star nod with a 14-6, 3.26 campaign in ’94. But after signing with St. Louis in ’95, he crashed back to earth with a 2-12 record and pitched only sparingly over the next two seasons.