Brazil's Guilherme Clezar has been fined £1,100 by the International Tennis Federation for a gesture he made during a Davis Cup match against Japan's Yuichi Sugita in Osaka.
After successfully challenging a line call, Clezar stretched his eyes in the direction of a line judge.
The 24-year-old said later he "never had the slightest intention to be aggressive, racist, prejudiced".
The ITF said it had fined Clezar for "unsportsmanlike conduct".
In a statement, it added: "The incident was reported after the match and the TV footage was then reviewed by the tie referee.
"Clezar issued a written apology.