ATLANTA — Aware of the upsets all around, the Atlanta Hawks really buckled down. They’d worked too hard for home-court advantage to let it slip away on the first night of playoffs.

With Josh Smith delivering one rim-shaking dunk after another and plenty of teammates chipping in, the Hawks made Miami look like a one-man team, running Dwyane Wade and the Heat ragged for a 90-64 blowout in Game 1 of their Eastern Conference series Sunday night.

Four other home teams—Boston, Portland, San Antonio and Orlando—had already lost about the time the Hawks took the court. Perhaps that spurred them on, because this one was over by halftime.

“We can’t worry about what anyone else is doing,” Joe Johnson said. “We’ve got to control our own destiny.”

For one night at least, they did just that by holding Wade to 19 points—11 below his NBA-leading average—and allowing only one other Miami player to reach double figures.

The Hawks tied a franchise record for fewest points allowed in a playoff game. Wade spent much of the night on his backside or complaining to the referees, his frustration growing as the Hawks raced to a 20-point lead by halftime in the opener to the best-of-seven series.

Game 2 is Wednesday night in Atlanta.

“Josh Smith got a lot of lobs and fast-break dunks that helped with the energy in the building,” Wade said. “When that happens, the game can get away from you pretty fast. When you miss as many shots as we did tonight, the game can get away from you pretty quickly.”

Miami was held to its fewest points of the season—its previous low was 68 — and the Hawks equaled the mark they set against the Charlotte Hornets in a 1998 playoff victory.

Smith scored 23 points and every other Atlanta starter also was in double figures. Wade made just 8 of 21 shots, and Michael Beasley added 10 points on a night in which the Heat showed its youth, shooting just 37 percent and managing seven points in the final period.

Wade, who took just two shots in the third quarter, compounded Miami’s problems by turning it over eight times.

“I’m criticized if I take all the shots. I’m criticized if I don’t,” he said. “We had some careless turnovers. I had a lot of them.”

The Hawks learned a year ago just how valuable that extra home game can be, facing Boston in their first playoff appearance in nine years. Atlanta made a series of it by winning three thrilling games at Philips Arena, but the Celtics won four blowouts in Boston to get started on their way to an NBA title.

From the day the Hawks walked off the court in Boston, they set a goal of gaining home-court advantage to start the playoffs. Atlanta came through, claiming the fourth spot in the East with its first winning record (47-35) in a decade.

Instead of opening in a hostile environment, the Hawks got to play in front of a raucous crowd that cheered their every move. They even brought out Atlanta-native T.I. to make the player introductions, the rap star still a month away from reporting to federal prison to serve his one-year-and-a-day sentence for pleading guilty to weapons charges.

“I didn’t know it would turn out THIS way,” coach Mike Woodson said with a grin. “I just thought our guys were so focused coming into tonight.”

Wade may have been the best player on the court, but the Hawks were much better overall. Smith led the way, firing everyone up with three thunderous dunks during a decisive second quarter in which the Hawks outscored the Heat 35-18 to build a 59-39 lead at halftime.

“I feel like we have the better team,” Smith said. “We’re not scared to play anybody.”

The Hawks made 11 of 16 (61 percent) in the second quarter, outrebounded the Heat 12-7, doled out eight assists and turned seven turnovers into 10 points. Miami shot just 39 percent (7 of 18), the final attempt a desperation heave by Wade, who ran into an Atlanta player on the follow-through and was sprawled out on the court as the horn sounded.

He got up slowly, clapped his hands in disgust and walked to the locker room.

Atlanta actually took control late in the first quarter. After Wade dunked coming off the baseline, the Hawks scored the final two baskets for a 24-21 lead.

The second period was no contest. With Wade getting a quick breather at the start, the Hawks quickly stretched their lead to 30-22. Then Smith took over, scoring 13 high-flying points before the quarter was done.

Al Horford blocked Wade at one end and the Hawks were off to the races, with Johnson lobbing to Smith for a thunderous jam. The former NBA dunk champion was just getting started.

His most spectacular play came off a lob by Mike Bibby, with Smith caught with his back to the hoop and slammed through while facing the other way.

“That,” Smith conceded, “was one of my good dunks.”

On the very next possession, the Hawks ran off a Wade miss and Smith rocked the house with another flying left-handed dunk.

“Josh really feeds off all the energy and pushes his game up to another level,” Horford said. And Smith’s teammates went along for the ride. “Oh, man, it really pumps us up when we get him going,” Horford added. “It gets us motivated to get stops and keep doing the right things.”

Miami rookie coach Erik Spoelstra got a rough initiation to the playoff game. He called three timeouts during the second quarter in a futile attempt to slow the Hawks, but all that seemed to do was give them a little extra rest so they could keep on running.

The Heat, who made a 28-win improvement over last season’s NBA-worst 15-67 team, looked more like the Miami, Version 2.008.

“Defensively, we were slow,” Spoelstra said. “We were slow in the mind, and whenever there seemed to be a loose ball or rebound, they seemed to have much more desperation than we did, and more physicality than we did.”

Bibby, whose acquisition at last season’s trade deadline gave Atlanta its first true point guard in years, ran the offense masterfully beyond just throwing up passes for the highlight shows. He dished out nine assists to go along with 10 points.

Smith had a double-double, also grabbing 10 rebounds. So did Hawks backup center Zaza Pachulia with 10 points and 10 rebounds.