The Nuggets held the Lakers to two points over the final 5:41 to extend their home winning streak to seven games.
"If we're going to win it's always going to come down to defense," Gary Harris said. "We were able to get stops when we needed them."
Denver was without its starting frontcourt of Nikola Jokic, Paul Millsap and Wilson Chandler. Millsap is out several months after surgery on his left wrist, Jokic was in a walking boot after suffering a sprained left ankle Thursday, but Chandler (back) could return Monday.
The Nuggets missed the trio, which combines for nearly 40 points and 21.2 rebounds per game. The Lakers outrebounded Denver 52-39, including an 18-7 advantage in the second quarter when Los Angeles took a 59-55 halftime lead.
"We practice with a lot of lineups. We know the offense, we know each other, our chemistry is growing," Murray said. "We know what everybody can do."
Brandon Ingram led the Lakers with 20 points and Brook Lopez had 15 points. Lonzo Ball had nine points, nine rebounds and five assists but couldn't duplicate the triple-double he had against the Nuggets at home on Nov. 19.
The Lakers took a 98-94 lead on Kyle Kuzma's 3-pointer but managed one field goal the rest of the way and had four turnovers. Barton and Murray led Denver's rally by combining for 20 of the 37 points in the fourth quarter.
"I thought a lot of what happened to us tonight was self-inflicted," Lakers coach Luke Walton said. "The exciting thing about that is if it's self-inflicted we can be the ones that change it."
Barton gave the Nuggets the lead for good with two free throws, Murray hit a 3-pointer to go up five and Denver closed it out.
"We just kept turning the ball over," Kuzma said. "We made a few costly turnovers and they converted."
Lakers: Kuzma was named the NBA Western Conference Rookie of the Month for November and games played in October. Kuzma ranked second among West rookies in rebounding (6.1) and third in 3-point field goal percentage (37.9). Kuzma returned to the lineup after missing Thursday's game with back spasms. ... The Lakers committed 21 turnovers.
Denver retired Lafayette "Fat" Lever's No. 12 in a halftime ceremony. Lever, who played for the Nuggets from 1984-90, recorded 43 triple-doubles in his career.
Lever is the sixth player to have his number retired by the Nuggets.
"I started thinking about (getting my number retired) when I was with the (Sacramento) Kings," Lever said. "I saw a lot of ceremonies that happened there. I thought `what if,' and what if came tonight."
Harris finished with 13 points, but his biggest bucket brought the crowd to its feet. With 8:41 left in the third Harris drove into the lane and started to go up for a layup. Ball cut off his path and Harris did a 360 and finished with a finger roll.
"Once I spun I was like, `Nah, this has to stay in my right hand the whole time. I'm not switching it up," Harris said.
The crowd cheered and his teammates were impressed.
"I was speechless. I didn't know what to do. It was a crazy play," Murray said.
Murray then shouted across the locker room to Harris, "I was open by the way." Harris quietly responded, "My bad."
Lakers: Host the Western Conference-leading Houston Rockets on Sunday night.
Nuggets: Begin a six-game trip in Dallas on Monday night.
More NBA basketball: https://apnews.com/tag/NBAbasketball
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