WASHINGTON — U.S. defender Oguchi Onyewu tore a tendon in his left knee during Wednesday night’s World Cup qualifier against Costa Rica, an injury that usually requires a recovery time of three-to-four months.

The AC Milan defender fell down on the slick turf of RFK Stadium during the 83rd minute of the 2-2 draw and left the field on a stretcher.
Because the U.S. had used its three substitutes, he could not be replaced. Still, the United States gained the draw when Jonathan Bornstein headed in a corner kick in the fifth minute of stopped time.
Onyewu was diagnosed with a torn patellar tendon.
A 6-foot-4 defender from Olney, Md., Onyewu left Belgium’s Standard Liege after last season and signed a three-year contract in July with AC Milan.
The 27-year-old has appeared in just one of the club’s 10 competitive matches this season, making his official debut as a 60th-minute substitute in the 1-0 Champions League loss to Zurich on Sept. 30.