Elson, who replaced the injured Kenyon Martin in the starting lineup, scored 10 points and grabbed 11 rebounds in the Nuggets' 100-84 victory over the lowly Charlotte Bobcats on Tuesday night.
Kleiza took advantage of more playing time with Eduardo Najera out after knee surgery and added a career-high 13 points off the bench.
"I don't think we win the game without LK's first half and Francisco's second half," Karl said.
Raymond Felton scored 14 points and had 11 assists to lead Charlotte, two days after being banged up in a minor car crash. Bernard Robinson, Jumaine Jones and Matt Carroll each added 13 for the Bobcats.
The Nuggets needed their supporting cast to beat the Bobcats, who started a six-game trip through the West with their fifth straight loss.
In the first half, Charlotte looked nothing like the team that has lost a league-worst 23 road games. They used a strong zone defense, forcing turnovers and off-balance shots from Denver, to build a 13-point lead early in the third quarter.
"Their zone messed us up, with our bad defense," Karl said. "And then we had bad turnovers, and then we had bad rebounding."
But the Nuggets started finding ways to overcome Charlotte's defense, while the Bobcats seemed to tire.
"Second half, I thought Andre [Miller] picked apart the zone more thoroughly," Karl said. "Our defense picked up. We made them miss a lot of shots and got our transition game going."
Anthony scored eight points and Buckner made a pair of 3-pointers during an 20-6 run to give the Nuggets a 68-67 lead with 3:36 remaining in the third.
"The beginning of the third quarter was atrocious," Bobcats coach Bernie Bickerstaff said.
The Bobcats kept it close until the beginning of the fourth quarter, when the Nuggets went on a 13-5 run, capped by a 3-pointer by Earl Boykins, to make 88-78 with 6:45 remaining.
"It's a good question of why we looked like two different teams in the halves," Carroll said. "They simply figured out our zone."
Charlotte scored 27 points in the second half on 10-of-37 shooting. The Nuggets grabbed 50 rebounds to the Bobcats' 40 -- the first time they've outrebounded an opponent in their last 12 games.
"We didn't want it to come down to the wire with a team like the Bobcats, we wanted to put them away early, and I think we did a good job of that in the third quarter, and early in the fourth quarter," Anthony said.
Buckner left the court with 1:33 left when he appeared to twist his right knee after being knocked by Marcus Camby under the Nuggets basket. The team said it was a hyperextension and listed him as day to day.
Najera started shooting around Monday after having arthroscopic surgery on his right knee on Feb. 13. He said he could be ready to play Friday, though team doctors may want him to wait a couple more days. ... Bickerstaff said forward Gerald Wallace plans to play Wednesday in Portland. Wallace has missed the last 14 games
with a left medial tibia bone bruise. "It's the medical people that are putting a hold on him," Bickerstaff said. ... Kleiza's
previous career high was 10 points, which he scored Jan. 20 against
Utah. ... Elson's double-double was his first this season.