Harrison threw six strikes among 11 pitches to four batters. He allowed one hit, a single up the middle by Mike Moustakas.
He has been slowed this spring training by a back problem. He received a nerve-block injection on the right side of his neck on Feb. 24, but was cleared for his back issue.
Harrison won 18 games and was an All-Star in 2012, then got a $55 million, five-year contract. He had never had any back issues before last spring training, and still made his first two scheduled starts. After going 0-2 with an 8.44 ERA, Harrison got two epidural injections and a second opinion before two operations in a matter of weeks.