Zurich - West Ham United were fined 100 000 Swiss francs by FIFA on Wednesday after playing Senegal striker Diafra Sakho in an FA Cup match despite his withdrawal from the Africa Cup of Nations (AFCON).
Sakho was called up to Senegal's AFCON squad in December but pulled out before the tournament began on January 17 due to a back injury.
However, since then he turned out for the Hammers in an FA Cup fourth round match on January 25 - scoring the winner in a 1-0 success over Bristol City.
Two days later Senegal were eliminated from the continental showpiece when coming third behind Ghana and Algeria in a tough qualifying group.
Senegal then complained to FIFA, football's world governing body, who opened disciplinary proceedings.
As well as West Ham being fined, both the English Premier League club and Sakho received reprimands.
FIFA's rules say a player cannot appear for his club if he is supposed to be on international duty.
"The FIFA disciplinary committee has found the club and the player to have violated... the regulations in relation to the match played by Sakho on 25 January. The club has been fined 100 000 Swiss francs and issued with a reprimand, while the player has been sanctioned with a reprimand," said FIFA's statement.
In reply, West Ham issued a brief statement of their own which said: "The club and the player have received the decision and will now be focusing their concentration on the game against Manchester United on Sunday."