Marsh will serve as the Royals' bulk reliever behind opener Austin Cox in Thursday's game in Boston, Anne Rogers of MLB.com reports.

EDGE Analysis

Since recording a career-high 11 strikeouts in his third MLB start July 15 versus the Rays, Marsh has labored over his last four outings (three starts), compiling an 8.31 ERA and 1.92 WHIP over that stretch while striking out no more than four batters on any occasion. The Royals will have Marsh enter the game behind an opener with the hope that the arrangement delivers better results from the young right-hander. If Marsh struggles again, however, he could be at risk of losing his spot in Kansas City's rotation.