"That's great," Nash said on Friday. "You love it when your best player has that confidence and that challenge. In a way, he's put it out for us to go get now."
Bryant said in an interview with Sports Illustrated that he is certain the Lakers will make the playoffs. The 15-time All-Star also claimed he has "no fear" of any potential postseason opponent in the competitive Western Conference.
"It's not a question of if we make the playoffs. We will," Bryant told Sports Illustrated. "And when we get there, I have no fear of anyone -- Oklahoma City, San Antonio, Denver ... whoever. I have zero nervousness about that."
When Nash was asked if he would like to offer a similar guarantee, he laughed.
"Yeah, I guarantee it, too," Nash said with smile. "What does it mean? Everyone guarantees something at some stage and everyone forgets. I feel the whole guarantee thing is ... I don't know. If I went and guaranteed it, would you guys care?"
D'Antoni said he wasn't big on guarantees but didn't mind Bryant making one, given the role he will play in making it a reality.
"He has a lot to say about it, so that's good," D'Antoni said. "I don't mind as long as we back it up. I don't mind at all. I think you have to have that mindset and I think everybody does. I'm not a guarantee kind of guy, but I'll let him do the talking since he's got to do the walking. Kobe's good enough. I'm with him all the way."
Like Bryant, Howard also believes the Lakers will be able to turn around their season and make the playoffs.
"I'm not going to sit up here and say, 'No, we're not going to make it,' " Howard said. "We got to have faith, and if we don't, we're not going to make it, but I believe that we're going to turn this around and we're going to be great."
Entering Friday night, the Lakers (26-29) had won six of their last nine games, including Wednesday's 113-99 victory over the Boston Celtics. Despite the recent hot streak, Los Angeles trails the Houston Rockets by 3½ games for the eighth spot in the conference standings.
Lakers general manager Mitch Kupchak thinks Bryant's confidence is "great," but recognizes making the playoffs will be an uphill climb.
"We dug a hole for ourselves. And we're going to need some help from teams that are in front of us. And we're going to have to play really good basketball ourselves," Kupchak said in an interview with ESPN's Stephen A. Smith. "But if we do get into the playoffs, that does mean that we're playing good basketball. And at that point, I'm very comfortable in a seven-game series with anybody, even if we get in at No. 8. I love Kobe's confidence and his vision for this team for the next three or four months.
"And that's what you need from one of your star players and one of your leaders, you've got to have someone that believes, and I think that's great."
Bryant, the NBA's fourth-leading scorer at 26.6 points per game, cited a loss earlier this month to the Miami Heat as one of the sources of his confidence.
The Lakers dropped a 107-97 decision in Miami on Feb. 10 to conclude a seven-game road trip.
Despite the loss, Bryant told Sports Illustrated the Lakers showed positive signs in the contest.
"We will make the playoffs," he said. "And we will compete. And part of the reason I have that confidence is the Miami game. We had control of the game. That was no fluke. We were playing very, very well. We were reading the defense, making the extra pass.
At Thursday's memorial service for Jerry Buss, who died on Monday, Bryant also encouraged his teammates to look at the players and coaches in the room and make the most of this season in the memory of the former Lakers owner.
"It would be great if we could use that as motivation," Nash said. "I'd like to think that regardless of Dr. Buss passing that we'd have the toughness to find it in ourselves to rally. It's been a tough year obviously, and trying, but we've made some progress and we have to continue to make progress the rest of the way. It would be a beautiful thing to do it for Dr. Buss."
Howard, who had visited Buss in the hospital after being traded to the Lakers, said he and most of his teammates already had that in mind before Bryant's speech.
"I think a lot of guys already felt that way anyway," Howard said. "So it wasn't nothing new. We've all been talking about doing something special and changing what's been going on here."