USC's inexperienced basketball team suffered a severe setback Thursday when guard Jio Fontan, one of the Trojans' two returning starters, was diagnosed with a torn anterior cruciate ligament in his left knee.
Fontan, USC's floor leader and top returning scorer, will require surgery and miss the 2011-12 season, Coach Kevin O'Neill said in by telephone from Brazil.
Fontan, a 6-foot senior from Paterson, N.J., was injured Tuesday night during an exhibition in Sao Paulo when he landed awkwardly after being hit in the air.
The Trojans are playing a series of scrimmages and exhibitions in Brazil, and are scheduled to play their final game of the trip Friday.
USC said X-rays taken Tuesday came back negative, but O'Neill said he feared the worst. Fontan returned to Los Angeles on Wednesday and an MRI exam revealed the tear.
"It's a huge blow for our team," O'Neill said.
Fontan scored 57 points in USC's first two games in Brazil. He averaged 10.5 points last season, starting every game after joining the team 10 games into the season.
NCAA transfer rules forced him to sit out until USC's Dec. 18 game at then-third-ranked Kansas, but he made an immediate impact, scoring 15 points as the Trojans lost in the final seconds. Three days later, he had 13 points as USC upset No. 19 Tennessee.
The Trojans' only other returning starter is Maurice Jones, a 5-7 sophomore point guard, who averaged 9.9 points last season.