And it didn't even take a full night's work.
"We're smart," Bosh said. "And we know how to play the correct way."
Dwyane Wade added 17 points, six rebounds and six assists for Miami, which used two big runs -- a 24-9 spurt to end the first half followed by an 18-3 flurry that closed the third quarter -- to snap the Suns' three-game winning streak. James also had nine assists and eight boards but deferred afterward to Bosh's breakout night.
"I think he was due -- well overdue -- for one of these games," James said.
Eddie House scored 15 points and Carlos Arroyo added 10 for Miami, which enjoyed its biggest win over Phoenix in nearly 14 years and held Suns point guard Steve Nash to an uncharacteristically low two assists.
"Well, we weren't necessarily expecting that result," Heat coach Erik Spoelstra said. "We just wanted to focus on our game, our energy and really having a defensive edge to us again. That's one of the most challenging teams to defend."
The top criticisms of the Heat this season, in no particular order, had been how they struggled against big-time point guards, how they couldn't seem to put teams away and that Bosh's numbers had taken a hit as he adjusted to his new role in Miami.
None of those issues were issues against the Suns.
"They just outplayed us the entire game," Nash said. "We only have ourselves to blame. We didn't play hard. We didn't play with enough aggressiveness or urgency and I think it showed."
Slowed by a sore groin, Nash scored 17 points for Phoenix. But the last time he had only two assists was Dec. 29, 2008, against the Oklahoma City Thunder, 141 games ago. And Wednesday marked only the ninth time in 737 games where Nash played at least 29 minutes and failed to get more than two assists, according to STATS LLC.
"I kind of took a little risk," said Nash, who may consider sitting out Thursday in Orlando. "It didn't feel great, but I don't think I did serious damage to it."
Controlling Nash, who came in averaging 12 assists in his last five games, was a huge point of emphasis for the Heat. In Miami's four losses this season, opposing point guards -- Rajon Rondo twice, Deron Williams and Chris Paul -- averaged 16.5 assists per game.
Bosh started quickly -- not a surprise given his recent history against Phoenix.
"When CB comes out as aggressive as he was, I think that helps us a lot," James said.
He hit his first four shots and had 14 points by the time the game was nine minutes old. He has topped 30 points in three of his last six meetings with Phoenix -- yet oddly hadn't been part of a win over the Suns since Feb. 10, 2004.
By the time Bosh went to the bench for the evening, snapping that streak was certain.
"We just never came close to guarding Bosh tonight," Suns coach Alvin Gentry said.
Miami wasted a 22-point home lead at home against Utah last week, and for a moment in the third quarter, the Heat seemed on the brink of blowing another huge edge. Phoenix frustrated Miami briefly with zone defense and Nash's finger-roll with 3:14 left in the third cut what had been a 25-point Miami edge minutes earlier to 82-70.
Some anxiety pulsed through the building.
"We didn't panic," Bosh said. "We didn't get out of place or anything. We just continued to play solid basketball."
Bosh scored the game's next seven points, kickstarting a run that put things away for Miami.
Reserve House hit a 3-pointer with 35 seconds left to get the lead back to 24, and Wade had a spectacular three-point play -- defensive rebound at one end, drive downcourt, finger-roll layup while getting fouled and then highstepping past photographers -- to make it 100-73 entering the fourth.
"We were focused in tonight," Wade said. "No matter what the score got to, I think we would have been fine."
Heat forward Juwan Howard, who was getting quality minutes for the first time this season, broke his nose. His availability for Friday against the Charlotte Bobcats is unclear. ... Suns center Earl Barron made his Phoenix debut, one day after signing with the club. Barron was part of Miami's 2006 NBA championship team.
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