Atlanta ? By now it has become inexcusable.

Zone defense is a way of life in the NBA. The Heat has yet to learn how to deal with it.

With Atlanta turning to a zone for salvation, the Hawks overcame a 19-point second-half deficit to humiliate the Heat 100-96 Thursday night at Philips Arena.

"When you don't think it can get any worse, it gets worse,'' said coach Pat Riley, his team now 5-21, with as many losses as he had in his second season with the franchise. "It's just ridiculous."

What was ridiculous was how the Heat reacted when Hawks coach Lon Kruger went to a zone. What had been a 73-54 Heat lead turned into a deficit when Hawks guard Dion Glover hit a go-ahead 3-pointer with 1:36 to play.

"When they went to the zone ... I don't know ... it messed us up,'' point guard Rod Strickland said.

Expect to see a steady diet of zone defense all the way to the lottery.

The Heat can't shoot, features a slow-moving variety of older players, and continues to practice a dinosaur offense when rules makers have mandated a move into the new millenium.

"They couldn't do much with it,'' said Hawks said Jason Terry, who went for 32 points and converted a decisive 12-foot jumper with 12.3 seconds to play. "We had younger guys on the floor, and we had more energy than they did."

Suddenly, the Heat's largest lead of the season stood as a mere inconvenience to Atlanta.

"It's a soft zone,'' an indignant Heat center Alonzo Mourning said. "We're supposed to handle it more aggressively, instead of playing passively."

Understand, this was the rare night when the Heat's offense was on, a night guard Eddie Jones went for 24 points, a night power forward Brian Grant broke out of a slump with 16 points and 11 rebounds. It was 35-18 after the first quarter, the most productive quarter of the season, and 58-48 at halftime, the Heat's most productive half in more than a year.

"We've got to have more desperate of an attitude,'' said Mourning, who finished with 14 points, eight rebounds and five blocked shots, but also was 0 for 6 from the foul line. "We didn't have it tonight. We should be sick with ourselves now."

With 16 points on 7-of-19 shooting in the fourth quarter, it all went south for the Heat, just like its season has from the first week.

The collapse left the Heat without a 100-point game this season, tying the franchise record with 26 consecutive games in double digits. The NBA record is 29 such games in a row.

Most confounding is that on a night the Heat finally established an offensive rhythm, Riley blamed the loss on the defense.

Even at 58-48 at halftime, Riley told his players, "The game's going to have to be in the 80s for us to win."

It is the mind-set of a team set in its ways, the mind-set of a team that fails to recognize the virtues of outscoring, a team that refuses to accept the realities of a brave new zone-defense world.

"They just dissected us in the second half,'' Grant said. "We just acted like we didn't know how to play. Or maybe we didn't know what we were doing in the last six to eight minutes. The second half, everything just broke down."

After Terry hit his jumper to make it 99-96, the Heat called time out with 12.3 seconds to play.

As has been the case so many times in late-game situations, the Heat could do no better than a scramble off the inbounds. This time is was forward LaPhonso Ellis coming up short on a 3-pointer, just as he did two weeks ago in Washington.

Said Terry, "They used to be the beast in the East."