The San Diego Chargers placed second-year linebacker Melvin Ingram on the physically unable to perform list Monday.

Ingram, the 18th overall selection in last year's draft, tore the ACL in his left knee during offseason training activities back in May and underwent successful surgery one week after to address the injury.

Ingram will miss at least the first six weeks of the season and is eligible to begin practicing any time after Week 6.

The 24-year-old University of South Carolina product compiled 41 tackles, one sack and five passes defensed while appearing in all 16 games and starting twice as a rookie last season.

The Chargers also placed cornerback Steve Williams (pectoral) and defensive tackle Byron Jerideau (shoulder) on the reserve/injured list.

Williams was a fifth-round selection this year and Jerideau was signed as a rookie free agent.