Liverpool forward Suso was fined £10,000 ($16,219) on Tuesday after labelling team-mate Jose Enrique "gay" on Twitter.
Suso sparked protests last month when he posted a photo on the micro-blogging website of Reds defender Enrique having his teeth whitened and added a tweet which read: "What f**k is he doing? This guy is gay...he does everything except play football."
He later deleted the tweet and uploaded the photo with a different comment, saying: "I dunno what to say..."
But the Football Association took exception to Suso's orginal comment and handed out the fine, while also warning the 19-year-old about his future conduct.
The FA said in a statement: "Following an independent regulatory commission hearing yesterday (Monday, December 17 2012), Liverpool's Jesus Fernandez Saez (Suso) has been fined £10,000 and warned as to his future conduct for a comment posted on Twitter.
"The charge, which the player admitted and requested a paper hearing, was that he acted in a way which was improper and/or brought the game into disrepute in that the comment was posted on his Twitter account and included a reference to a person/s sexual orientation and/or disability."
Suso had made a promising start to his Liverpool career after moving to Anfield from Cadiz in the close-season.
The Spain Under-21 international has made 13 appearances for Brendan Rodgers' side, including six starts in the Premier League.