Moala's knee injury is a torn ACL, according to ESPN NFL Insider Adam Schefter.
It's the third straight year Moala has finished the season on injured reserve. In March, the defensive end re-signed with Indianapolis after posting a career-best 26 tackles. He also had 1½ sacks and fumble recovery in 2013 but landed on IR with a knee injury just before the playoffs started.
The scare came when Hilton fell to the ground during a light workout and came up clutching his right leg. A few minutes later, he got up, stretched out and eventually returned to practice. He told reporters he was OK.
To replace Moala, Indy signed 6-foot-4, 280-pound defensive end Gannon Conway, an undrafted rookie.