CHARLOTTE—The mood around the Carolina Panthers facility on Monday reflected the gray, rainy weather outside: a little gloomy, a bit resigned, and hoping for a fresh, clean slate once the rain has cleared.

Rookie running back Jonathon Brooks suffered a torn ACL in his right knee on Sunday, re-tearing the same one that he had worked the past year to come back from.

"My heart is with him," coach Dave Canales began as he shared the news Monday afternoon. "I mean, just the amount of hard work that he put in to get back to this place to get him to play, so he's heartbroken. I'm heartbroken, the whole group just feeling for him, you know. So, we'll be here every step of the way with him, supporting him through this journey."

Brooks had played in only three games this season after spending the past year coming back from the same injury suffered in his final year at Texas.

"He knows how to do this," Canales pointed out. "He'll be able to attack it, and his focus is just going to shift in terms of what he's competing for. So, just again, it's definitely hard on JB right now. All of our thoughts are with him."

Canales shared the news with his team in the Monday meeting. Despite Brooks playing so few games, carrying the ball nine times for 22 yards, he had quickly endeared himself to his new teammates through his commitment to getting back on the field and what he'd done on it since.

"Devastating man," offensive lineman Robert Hunt admitted. "It was sad to see. I went to him yesterday after the game and talked to him. I was hoping it wasn't what it was.

"It's sad, man, for a kid to put that much work in to come back and, you know, obviously looks good in my eyes, a lot of people, you can see the talent that he does have for it to be that way, man."

As Brooks has integrated himself into the offense and the running back corps, he has become especially close with Chuba Hubbard. The veteran has taken Brooks under his wing, often giving him individual attention during practice, helping him adapt quicker to the league. Sunday was a poignant day for Hubbard, who eclipsed the 1,000-yard mark for the first time in his career but also saw his friend and teammate carted off the field.

The moment Brooks went down on the field, Hubbard was the first person to him, coming off the sideline to check on the rookie.

"JB is my guy," Hubbard said Monday. "Just see how hard he's worked to get back and all the work he's put in. Obviously, your mind wants to go a bunch of different places, but he just turned to God in these types of moments, and JB's resilient; he'll be all right; he'll fight back.

"I know he's hurting, but we got his back right now. He'll be back, and that's all important. That's most important. When adversity hits, for me especially, I just turn to God, and I know he'll do the same, and like I said, he'll be back greater than ever.

"I mean, that's my dog, like I said, been checking up on him ever since it happened and just making sure he's good, and he told me the news. Obviously, I was heartbroken for him. It's not an easy thing to deal with. But like I said, he's resilient, he's tough. He can get through anything that's thrown at him. So I know this will only make him better."

Running back unit takes double whammy

The running back unit as a whole took a hit on Sunday, with Raheem Blackshear exiting the game as well with a chest injury. He was taken to a local hospital in Philadelphia as a precaution to rule out anything serious. Canales told reporters on Monday that it was a blunt-force contusion.

The plan for now is to elevate Mike Boone from the practice squad, and Canales shared that "we're looking at all (options)" on the open market.

"Mike Boone, who's been with us this whole time, we'll ask Mike to help us out that way," Canales said. "And then we'll have to see where we're at with Raheem."

Boone entered the league in 2018—making him the most experienced guy in the Panthers running back room—and spent the first three years of his career with the Vikings. From there, he spent two years with the Broncos and had a stop with the Texans as well before coming to Charlotte this offseason.

He has spent most of this season on the practice squad, appearing in only two games, carrying the ball four times for 7 yards. It's the smallest sample size he has had in a season. He had two seasons appearing in all 16 games, two seasons with nine games, and two with eight games.

Spending a season on the P-squad has allowed Boone a 30,000-foot view at the offense and his own game.

"That just helped me hone in on the small details, just give more reps at what we do every day, you know, it's been good," Boone shared Monday. "I've been elevating my game behind the scenes too, so I'm looking forward to (it).

"When we're playing our brand of football, we're a good team. We got a lot of weapons and a lot of guys we can throw the ball to. Chuba, we can hand the ball. As long as we're playing our ball and our style of offense, we're solid.

"I want to be another tool, another weapon for our offense…if that's being out the backfield, between the tackles, you know, lining up wide, whatever, I feel like I can be on that.

Added Hubbard: "One thing about our running back room is every single guy is on their stuff and wants to be great in their own way. We all know the roles that we fit on this team and one thing that we hold ourselves to a high standard is just always being ready no matter what the situation.

"So, Mike's been ready for this moment, he'll do great and I'm looking forward to it for him."

Jaycee Horn and other injury updates

For a team that had been getting healthy, Sunday brought a rash of injuries. Cornerback Jaycee Horn left the game with a groin injury.

Canales said he is day-to-day but that the news "checked out better than, it's checked out pretty good for what we hoped coming out of the game."

Horn has played 100 percent of the snaps in eight games this season. Prior to Sunday, when he was forced to leave early, the only other games in which he missed some snaps were blowout scores.

"But again, we have to just take it day by day and kind of see what his availability will be like this week," Canales said.

Rookie Jalen Coker will try to go again this week. The receiver has been dealing with a quad injury the last three games.

"Just progressing through with the quad," Canales said as an update. "(He) had another session today. So we'll regroup and talk about what that looked like today and hoping to get him back out there this week."