A composed central defender, Onyewu has spent his entire professional career in Europe. He left college football to sign a four-year deal with Metz in 2002, having impressed during the 2001 FIFA World Youth Championship. He struggled to make an impact in France and was loaned out to Belgian sides La Louviere and Standard Liege. His performances for Liege prompted them to sign him on a permanent basis and he is now recognised as one of the most promising players in the Jupiler League. Onyewu made his senior international debut against Panama in October 2004 and was a member of the USA's 2005 CONCACAF Gold Cup winning team, as well as featuring regularly during the qualifying campaign for Germany 2006.