The USA stopper will not earn a salary in his final Milan season.
Onyewu has been out since October, when he tore a patella tendon during a United States CONCACAF match against Costa Rica.
His old deal was set to expire in 2012, but he has agreed to play on for an extra year. And, for retrenching Milan, his offer of playing for free has come as good news.
A statement on their official website reads:
"United States national team player Oguchi Onyewu, who has been injured for most of the season, but is ready to play for his country at the World Cup, has today been a protagonist on a human and professional level.
"Assisted by his agent Jean Louis Dupont, Onyewu asked for - and obtained - a one-year extension to his current deal from June 30, 2012, to June 30, 2013.
"In the course of this extra year, Oguchi, based on his own decision, and appreciated by the club, has asked not to earn any type of remuneration. Oguchi's gesture is exemplary, and deserves sincere congratulations."
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