LOS ANGELES -- Kyle Kuzma scored 17 points in the fourth quarter, showing off a spectacular array of big shots and slick passes.
"That's why we've got practice tomorrow," Kuzma said with a grin.
The Lakers still have much to learn, but they took another major step with a victory in this hallowed NBA rivalry.
Kuzma scored 28 points and the surging Lakers sent the Celtics to their fourth consecutive loss, 108-107 Tuesday night.
Jordan Clarkson scored 22 points in the sixth consecutive home win by the Lakers, who have won three straight and seven of nine overall during their best stretch of the season.
Kuzma hit five 3-pointers and dominated down the stretch, yet Los Angeles nearly gave it away by missing 10 of its 17 free throws in the fourth quarter, including four in the final 20 seconds. The Lakers are the NBA's worst team at the free-throw line and also at the 3-point line, where Kuzma's teammates were a combined 2 for 19 -- which made this win all the more improbable to coach Luke Walton.
"I have confidence that those guys that missed them tonight will make them in the future," Walton said. "But hopefully we can remedy that sooner rather than later."
Kyrie Irving scored 33 points for the Eastern Conference-leading Celtics, who opened a four-game road trip by extending their longest losing streak in nearly two years. Smart added 22 points and led the Celtics back.
Kentavious Caldwell-Pope missed two free throws for Los Angeles with 5.7 seconds left, but Smart's final miss over Caldwell-Pope's defense allowed Los Angeles to snap a four-game losing streak against Boston.
"It was a great game for us to learn from," Irving said. "Minor details, you know? Getting offensive rebounds and blocking out. Taking opportunities to force them into tough shots."
Irving led the Celtics back within two points late, but Kuzma and Julius Randle came up with big baskets on offensive rebounds. Smart then hit two free throws for Boston with 19.2 seconds left after Josh Hart missed two for LA, trimming the lead to 106-105.
Clarkson hit two free throws, and Terry Rozier hit a twisting layup with seven seconds left before Caldwell-Pope's misses.
Celtics: Al Horford returned with 13 points and 12 rebounds after missing the last game in the concussion protocol after taking an elbow to the head. ... Boston beat the Lakers 107-96 on Nov. 8.
Lakers: Caldwell-Pope (right heel) and Brandon Ingram (sprained left ankle) played after being questionable before game time. Ingram had seven points on 2-for-11 shooting. ... Kuzma has 15 20-point games this season, the most by a Lakers rookie since Eddie George in 1995. ... Fans near courtside included Ryan Leaf, Dodgers stars Kenley Jansen and Yasiel Puig, and comedian Nick Kroll.
Gordon Hayward was with the Celtics after traveling to Los Angeles last week. He will stay in town for the next 7-10 days to continue his rehabilitation from his horrifying left ankle injury just five minutes into the season. Boston coach Brad Stevens said the move is designed "just to mix it up" during Hayward's extensive rehab, which is still proceeding on schedule. Stevens said Hayward could begin traveling with the team full-time by early March as he continues to work toward a return. Until then, he'll watch practice from the sidelines while staying as stationary as possible. "He's a really good spot-up shooter," Stevens said with a grin.
Kuzma, the Lakers' impressive rookie forward from Utah, had his best offensive game since Christmas. He put the Lakers ahead during a 3 1/2-minute stretch of the fourth quarter with 13 points and a behind-the-back assist to Larry Nance Jr. for a dunk that brought Staples Center to its feet. He added four rebounds and three assists without and turnover and did it all in less than 27 minutes of play. "His fourth quarter was incredible," Walton said.
Lonzo Ball missed his fifth consecutive game with a sore left knee for the Lakers, but they've developed a solid offensive approach in the absence of the rookie point guard. Replacements Tyler Ennis and Alex Caruso contributed little offensively, but Clarkson had another outstanding playmaking game, and Randle contributed 14 points and 14 rebounds.
Celtics: Stay in LA to face the Clippers at Staples Center on Wednesday night.
Lakers: At the Chicago Bulls on Friday night to open a five-game road trip. LA plays 11 of its next 14 on the road.
More AP NBA: www.apnews.com/tags/NBAbasketball
How the Trail Blazers recovered from that shocking sweep
Portland has started hot after last season's playoff collapse. But how high is this team's ceiling?
Gritty Clippers face Wizards next
The Los Angeles Clippers come rolling into the Nation's Capital Tuesday night to face a Wizards team in disarray.
Trail Blazers-Knicks Preview
After dropping 40 points on the Washington Wizards in a 119-109 win on Sunday night, Damian Lillard follows with an encore at Madison Square Garden, where the Portland Trail Blazers travel to take on the New York Knicks at 7:30 p.m. on Tuesday.