Panthers' Jonathon Brooks, D.J. Wonnum out at least 4 games

CHARLOTTE, N.C. -- Carolina Panthers rookie running back Jonathon Brooks and outside linebacker D.J. Wonnum will miss at least the first four games of the season, it was announced Tuesday.

Brooks will remain on the non-football injury list, while Wonnum will start the season on the physically unable to perform list.

The Panthers on Tuesday also released receiver Terrace Marshall Jr.

Brooks has not practiced since Carolina traded draft picks Nos. 52, 142 and 155 to the Indianapolis Colts to select the Texasstar at No. 46 in April. He's still recovering from ACL surgery in November after injuring his right knee against TCU.

Wonnum was signed to a two-year, $12.25 million deal in March after spending his first four seasons with the Minnesota Vikings. He was slated to be the team's starting outside linebacker opposite Jadeveon Clowney, but continues to rehab from quad surgery in December.

Carolina will open with D.J. Johnson, Eku Leota and K'Lavon Chaisson opposite Clowney, but could add others after cuts.

The team has the top pick off the waiver wire after going an NFL-worst 2-15 last season.

Panthers coach Dave Canales has been adamant that Brooks is on the right track, but that it's more important to be patient and not rush him back. He said early during training camp that Brooks likely wouldn't be ready until Week 3 or 4, at the earliest.

Brooks, when he last spoke to reporters during offseason workouts, seemingly understands.

"You kind of just have to look at your future,'' Brooks said at the time. "I just have to know that for me to have patience is going to help me further my career.''

Chuba Hubbard, in the last year of his contract, will open the season as the starter. He will be backed up by Miles Sanders, who lost the starting job last season.

Marshall, a former second-round pick, caught 19 passes for 139 yards for the Panthers last season. The team explored a trade for him but nothing panned out, a source told ESPN.

Panthers quarterback Bryce Young had nothing but good things to say about Marshall.

"I see someone who works extremely hard, cares always, the last person on the field leaving,'' Young said. "On the field, I've seen so much growth. ... That's someone I believe in tremendously, someone who will be a good addition to any room. I have the utmost confidence he'll have success in the future.''

Outside linebacker Amare Barno also will open the season on the PUP list while recovering from knee surgery.