Onyewu, who landed awkwardly on his knee late in the USA's qualifier against Costa Rica on Oct. 14, was initially projected to face a his recovery period of three-four months. The new estimate came after national team physician Dr. Bert Mandelbaum operated on Onyewu.
A six-month layoff would mean Onyewu could be ready to return to action for AC Milan in mid-April -- just a month before the Serie A season ends May 9.
The loss of Onyewu, the USA's most indispensable defender, would be severe blow. His absence from the home qualifier against El Salvador in September -- the only Hexagonal game he missed -- was certainly felt.
Onyewu's injury came a day after forward Charlie Davies' chances of playing in the World Cup were almost certainly wiped out when he sustained serious injuries in a car crash.
As it is, Jay DeMerit, Onyewu's partner in the middle of the U.S. defense during its strong Confederations Cup run, just had a cornea replacement operation and is also sidelined.