With veteran duo LeBron James and Rajon Rondo out injured, Luke Walton has urged other Los Angeles Lakers players to fill the leadership void.

The Lakers went down 119-112 to the New York Knicks at Staples Center on Friday, their fourth loss in five matches since James sustained a groin strain against the Golden State Warriors.

James will miss the Lakers' next two games and be reassessed next week, while Rondo is not expected to be back until February after having surgery on his finger.

After seeing his team surrender a six-point advantage in the fourth quarter against the Knicks, Walton wants to see greater maturity from his young core.

"It's got to come from the group. We know we have some of the best leaders in the game. We've got LeBron, Rondo and Tyson [Chandler], but they're hurt so it's up to other people to step up and lead," said Walton.

"Guys are doing it, we just have to do more of it. It's great when things are going well. The challenge is when we hit dry spells or other teams get hot, that's when it starts getting quiet.

"That's when we need it the most. That's when we need five guys huddling up on the court talking about what happened on the last play, what's going to happen on the next play. Being in the moment of playing.

"That's something that normally comes with age. We're playing a lot of young guys right now, but that's where we're at and we trust and we believe that the guys playing can win. We just have to do it."

Walton felt the Lakers broke away from a team ethic as they came under pressure in the fourth quarter, with too many individuals attempting solo plays.

"Until we accept that the team is the most important thing – and I can't tell if it's because we're missing open shots and layups if you will that we stop trusting each other," he said.

"But the ball was moving beautifully when we built up our lead then we got to the fourth and we had a couple possessions of nice ball movement and then when shots didn't go in, guys start trying to do it on their own and that's not a recipe for us to win.

"For what we're playing with and the amount of injuries we have to guys who are a huge part of what we do, we've got to play for one another, the guys that are out there on the court. It cost us again in the fourth quarter. A little frustrating, but no one's feeling sorry for us."

JaVale McGee was one of the Lakers' other veterans on the court and the towering centre acknowledged leadership responsibilities must be picked up elsewhere with big names out of commission.

"We've got to step up. Everybody, as a team. We've got to step up, there's no excuse. We are professionals, we know how to play basketball, so we just got to come together and step up," said McGee.