Philadelphia Union defender Kai Wagner was hit with a three-match suspension on Tuesday for violating Major League Soccer's on-field anti-discrimination rules, the league said.
Wagner, 26, is alleged to have directed a racist slur at New England Revolution player Bobby Wood during their playoff clash on October 28.
MLS said Wagner's three-game suspension was effective immediately, ruling him out of Wednesday's return fixture against the Revs.
The league said Wagner would serve the remaining two games of the suspension in this season's playoffs. If Union are eliminated, Wagner will miss any remaining game at the start of the 2024 season.
MLS said Wagner was required to participate in league-mandated education and training sessions over the incident.
US media reports say Wagner is alleged to have directed a German word considered racist towards Asians during his clash with Wood.
Former US international Wood speaks fluent German, having played in Germany for 14 years at youth and senior level.