Julian Green of the second-tier Bundesliga team, Greuther Fürth, faced racial abuse during the first round of the German Cup against Hallescher FC in Halle on Saturday.
During the match, some spectators hurled racial slurs at Green, but he did not let them bother him and did not report the incident to the referee.
"I didn't want us to get rattled because I really wanted to win here," the footballer, who had also played for the United States national team, said.
Fuerth beat third-tier Hallescher FC 1-0.
Coach calls on fans to stand up to racism
Greuther Fürth coach, Alexander Zorniger, said he was frustrated that spectators around them did not rebuke those who hurled the abuse.
"If someone says monkey to a player for the third or fourth time, then I just have to say: shut up! I can't hear it anymore," he said in a post-match news conference.
"The stadium was 95% full. There were enough people there who could have intervened," he added.
Hallescher spokeswomen Lisa Schöppe apologized on behalf of the club for the behavior of some spectators.