Roy Hemsley, an offensive lineman from Los Angeles Windward School, visited USC on Tuesday and signed a financial-aid agreement.
"I wanted to get it out of the way and make it official," said Hemsley, who committed to USC in May.
Hemsley, 6 feet 6 and 270 pounds, is on track to enroll in January. He said he has closed his recruitment and his only official visit will be to USC.
Hemsley said he could not pass on the opportunity to attend USC.
"I've always been a fan," he said. "I love the coaching staff, they are really great guys, and I'm good with the decision I've made."
Hemsley is the second offensive lineman in the 2015 class to sign a financial-aid agreement with USC, joining Chuma Edoga from Georgia.