The Lakers inflicted a first home defeat of the NBA season on the Heat, but a 13th straight road win looked unlikely when they trailed by 14 points in the first half.
James dropped well short of his usual sky-high standards in that opening half, turning the ball over seven times and missing seven of his 11 shots.
The four-time MVP was transformed in the second half, though, finishing with 28 points, 12 assists and nine rebounds as the Western Conference leaders won a thriller to move to 23-3.
James revealed some frank words from his colleagues were justified.
"Well, we were down today because of me," he told ESPN. "I was reckless.
"My team-mates got on my ass. They told me you're playing too passive, thinking about the game way too much instead of reading and reacting and doing what you do. Anthony Davis got on me, Boogie Cousins got on me and they told me to just be me.
“Felt like a heavyweight bout. Old-school Foreman-Ali or Tyson-Holyfield.” 🥊🥊 pic.twitter.com/FCLtq8OcxA— Los Angeles Lakers (@Lakers) December 14, 2019
"So I was like, 'Thank God we have two halves in a basketball game,' where I can flush the first one, and then come back and try to help us win."
Davis also played a major part in the Lakers' turnaround, racking up 33 points and 10 rebounds.
He said: "We knew it was going to be a dog fight, that's what it was tonight and the game was fun. These are the types of games we live for."