Coach Erik Spoelstra said the decision, announced less than two hours before tipoff, was "somewhat close." But after Miami beat Chicago 93-79, Spoelstra said he didn't want to risk James aggravating the injury.
"One serious hit to the face would have been very tough," Spoelstra said. "It would have been a big setback."
James was replaced in the lineup by center Greg Oden, who made his first NBA start since December 2009.
James has been in top form lately, scoring at least 33 points in each of the past four games, all wins. But he had no problem with the decision to keep him on the bench, Spoelstra said.
"He didn't stand up and put up his dukes and fight us," the coach said. "We still understand the big picture. The fact that we don't play until Thursday, it makes the most sense."
James broke his nose midway through the fourth quarter of Thursday's victory at Oklahoma City and sat out the rest of the game. His nose was reset by a doctor Friday and he missed practice Saturday.
Even if James returns for the Heat's home game Thursday against the New York Knicks, he'll get a week off — a rare idle stretch for one of the NBA's most durable stars.
"It doesn't hurt at all," teammate Dwyane Wade said. "When you're in such a great rhythm, you don't want anything to stop that. But at the same time, to get this time off to regroup, when he comes back on the court — hopefully Thursday — he'll feel a little fresher. That'll take him to the end of the season for sure. He doesn't need much."
The only other game James missed this season was in December, when he sat out because of a groin injury while the Heat won at Portland.
ODEN STARTS
Earlier this season, Greg Oden made his first basketball appearance in four years.
Today, with LeBron James out for a broken nose, Oden got the start for the Miami Heat, which was the first time he has been out for opening tip since the 2009-10 season. Oden produced five points and five rebounds in 13 minutes on Sunday.
Oden, a former No. 1 pick, has dealt with serious knee injuries over the years, but he remained determined to get back on the basketball court.
While Oden only averages 7.8 minutes per game, he has shown flashes of the player he used to be on occasion, putting down that patented two-handed dunk more than once. So far Oden has averaged 2.8 points and 2.2 rebounds in those limited minutes.
DRIVING LESSONS
Milwaukee Bucks wing Giannis Antetokoumpo may be part of the NBA's up-and-coming crop of stars, but he still has to do things that normal teenagers do.
One of those things is practicing for his upcoming drivers' license test, as seen in this video.
And yes, he keeps those monster hands at "2 and 10" — they take up basically the entire steering wheel. While he's logging the practice miles on the road, he asks assistant video coordinator Ross Geiger what noise a deer makes.
OTHER INJURIES
Thunder center Kendrick Perkins missed Sunday's game against the Los Angeles Clippers with a strained left groin.
Perkins was injured during the third quarter of Oklahoma City's loss to Miami on Thursday night. He has averaged 3.4 points and 5.0 rebounds in 54 starts. Steven Adams, a rookie, got his third career start in Perkins' place. He scored one point and grabbed six rebounds in 16 minutes.
Clippers guard J.J Redick remained out with a bulging disc in his lower back. He had missed the previous six games. He has played in just 30 games this season while dealing with wrist, hip and back injuries. He averages 15.7 points and 2.2 assists per game.
Contributors: DeAntae Prince, Kami Mattioli, The Associated Press