They wore white, in keeping with the team's "White Hot Heat" theme. Some were in costume: fright wigs, basketball caps, rubber suits and face paint. They took pictures of each other, yelled cheers together and predicted victory.
"People said it couldn't be done in the first season, but they showed up, and did what needed to be done," said Shane McKendrick, 21, a University of Central Florida student from Plantation.
The "they" McKendrick spoke of, of course, were the Big Three — LeBron James, Dwyane Wade and Chris Bosh — who promised to lead the franchise to its second NBA title.
"One steps up when the others can't," said McKendrick. "So I feel pretty confident about this."
Next to McKendrick was his 13-year-old brother Kyle holding a handmade sign: "Let's Go Heat."
"I just love basketball," said Kyle.
Indeed, all of South Florida seems to love basketball this week, as the Heat squared off against the Dallas Mavericks in a best of seven series that promises to be one of the most-hyped Finals in history.
"We're going to be a really good team," said James when he went on ESPN in July to announce "The Decision."
Later the All-Star forward promised "Not two, not three ... four ... five ... six ... seven," meaning championships. "I'm not up here just blowing smoke."
Smoke or not, the teaming of James and Bosh with Wade has had a huge impact on the sports climate of South Florida, said Alyce Robertson, director of the Downtown Development Authority. "Last week we had 10,000 people here to watch the game outside the arena when the team was in Chicago," she said. "The team has caught fire. They are living up to their name."
Dennis Drucker and his son Daniel left their home in Coral Springs and arrived at the arena three hours before the 9 p.m. tipoff. "We came early just to soak up the atmosphere," said Drucker, 54, director of operations for an Ed Morse auto dealership.
His tickets came from his son as surprise early Father's Day gift.
"To see all this excitement, the media, the satellite trucks — it's just exciting," he said.
Not everyone in the throng gathered outside the arena's doors had tickets for the game. Gelsyn Martinez, 35, a New Jersey resident in town on vacation, said he showed up "just to share in the adventure.
"I'm not even a sports fan," said Martrinez, a native of Brazil. "But this is exciting for me. It's like Carnival."
Tickets were available, at the box office through Tuesday morning, from marketplace sites such as Stub Hub, and from scalpers on the street. Daniel Drucker, 21, a recent graduate of the University of Miami, said he paid $148 each for his two upper level seats on Stub Hub.
Among the more outlandish outfits sported by fans was the handmade suit worn by Christopher Brown, 36, of Coral Springs, a season ticket holder who attracted a bevy of camera-wielding folks who just wanted to snap his picture.
His red-and-white suit was studded with spangles and he wore a silver Heat grill in his mouth. He held a sign that read, "In Miami we smoke Cubans," a wry reference to Mavericks owner Mark Cuban.
"When LeBron said he was coming to South Beach, that was the happiest day of my life," said Brown, a graphic designer. "I'm a native of South Florida and I just love that this is happening here."
There were even some Dallas fans in the house brave enough to wear their colors. "We've been hearing it from the minute we stepped out of the car," said Chad Gray, 31, a Texas native who lives in Parkland, at the game with his brother and two friends.
"But we're true blue," said Gray, wearing a vintage Jamal Mashburn jersey.
Greg Morris, 58, of Fort Lauderdale, said he hoped to be at the arena for the Finals when he bought his season tickets a year ago, but he admitted that the Heat's success was not a sure thing.
"I thought we'd make it to the conference finals for sure, but this is something," said Moirris, there with his 21-year-old niece Jaclyn Morris, an accountant.
"Fortunately," said Greg Morris, "I'm retired. So I'm a full-time Heat fan now."