UPDATE: Here is a little more
from the OCR:
Onlookers said Sanchez was throwing the ball to teammate Clay Matthews, hopped after completing the toss, landed awkwardly on his foot and twisted his knee.
?He was all by himself,? USC coach Pete Carroll said. ?It was a silly thing that happened.?
Carroll did not know the severity of the injury but said he hoped to have news sometime tonight. About 6:25 p.m., offensive coordinator Steve Sarkisian said a doctor was on his way to examine Sanchez?s knee and give a preliminary diagnosis.
About a half-hour after practice, Sanchez emerged from an SUV on crutches with a large black brace on his left knee. He used the crutches to slowly make his way into the USC locker room.