LOS ANGELES -- The NCAA on Monday opened an investigation into whether former USC basketball player O.J. Mayo received tens of thousands of dollars in cash and benefits from an agent's representative before and during the one season he played for the Trojans.

The allegations were made by former Mayo confidant Louis Johnson during a segment of the ESPN show "Outside the Lines" broadcast Sunday.

USC responded to the report by releasing a statement Sunday saying that the NCAA and Pacific 10 Conference had reviewed Mayo's situation before and during his enrollment at USC "and did not identify any amateurism violations."

That review, conducted by the school's compliance office in conjunction with conference and NCAA authorities, was extensive with a scope far beyond perfunctory NCAA Clearinghouse procedures, said a source with knowledge of the situation who wouldn't speak unless guaranteed anonymity.

In its own statement to the Los Angeles Times on Monday, the NCAA said the allegations made on the television show were "new to the NCAA. This information was not available when the NCAA examined Mr. Mayo's academic and amateurism status prior to his collegiate enrollment, and we will review the information in conjunction with the institution and the Pac-10 conference."