Kevin Ellison, a former USC player, died at age 31.(Photo: Christian Petersen, Getty Images)

LOS ANGELES – Former Southern California defenseman Kevin Ellison, captain of the Trojans before a brief career in the NFL, has died. He was 31 years old.

The USC Sports Department confirmed Ellison's death with a Twitter post on Saturday. the According to the Los Angeles Times, records from the Los Angeles County Coroner's Office showed that Ellison had died on a highway, although no cause of death had been given and that no one was killed. an examination is still pending. Ellison's brother, Chris Ellison, told the Times that his brother had mental problems and that he was walking along the I-5 at the time of his death.

Kevin Ellison played for USC from 2005 to 2008. He was an all-pac-12 security player and played in teams that won three Rose Bowl games.

Ellison was selected by San Diego in the sixth round in 2009 and has played nine games in the NFL.