Kevin Garnett was informed Tuesday before practice that former NBA star-turned-national TV analyst Magic Johnson doesn’t think the Celtics have much of a chance to compete without Rajon Rondo the rest of the season.

Garnett’s response?

“Who cares? Who cares? To be honest, who cares?” Garnett said, finishing with a devilish smile.

The Celtics began the serious business of trying to move on without their star point guard on Tuesday, holding practice as they get ready for the Kings Wednesday at TD Garden.

“Everybody knows the responsibility on most of the people,” Garnett said. “It’s not going to be one or two guys to carry this thing, or carry his load. It’s going to be a bunch of people. This is a different group. We’ll see soon. We’ll see how we react to all of it.”

“We have a system that runs a certain way. It’s predicated when guys are on in and predicated when guys are out. As long as you run the system the way it supposed to go, it’s not perfect but it never skips a beat. It’s when we don’t do things as a team we struggle. Rondo is a huge part of this team. We all know that. Like I keep echoing, it’s not going to be one or two people, it’s going to be team effort.”

Garnett admitted that the news Sunday really put him and his teammates in a funk.

“To be honest, I think everybody was in a fog almost,” Garnett said. “I think it’s kind of settling in and I think everybody is trying to put their arms around the concept that he’s actually hurt, hurt to the point where he can’t play. That’s what had everybody in a fog, even him. He came in this morning and seeing him in there was kind of unreal. The fact that it is real, everybody is going to consolidate and pick up the pieces and try to carry this thing.”

Garnett said he and veterans like Paul Pierce and Jason Terry will do what they can to help Rondo through this difficult time as he gets ready for surgery on his right knee. Rondo was at the team’s facility Tuesday but Garnett said Rondo wasn’t there to provide support to his teammates.

“I think it’s the other way around,” Garnett said. “I think right now we’re being more a support system for him, giving him what he needs, especially some of the veterans who’ve had surgery, giving him advice and expertise.”