They would not lose on this night, of all nights.

Not when, beforehand, standing in front of a sold-out Spectrum crowd, the legend known as Julius Erving demanded these 76ers beat the Chicago Bulls just like his teams used to do.

This may be a season of ups-and-downs, but losing would be too cruel a down.

They flirted with it - these Sixers did - but they beat Chicago, 104-101, in what will be the franchise's final game at the proud Wachovia Spectrum.

It took an end-of-game flurry - a free throw, a blocked shot, a just-missed three-pointer, a final rebound - but these Sixers did as Erving demanded.

"This is a must-win game, with guys like that in the building," said Sixers forward Thaddeus Young.

The Sixers improved to 32-31, and tied the Detroit Pistons for the sixth spot in the Eastern Conference. Chicago drops to 29-37 and slips farther from the eighth playoff spot, currently held by the Milwaukee Bucks.

Despite the Sixers building a lead by as many as 13 points in the fourth quarter, Chicago tied the score at 101-101 on a broken-play three-pointer by guard Ben Gordon with 36.7 seconds left.

With 22.1 seconds left, swingman Andre Iguodala made 1 of 2 free throws for a 102-101 lead.

Sixers center Samuel Dalembert then blocked the shot of rookie guard Derrick Rose (20 points). Iguodala corralled the ball and passed upcourt to Young, who paused for a second, then dunked for the final margin.

When Gordon's last-second three-pointer from the right wing rimmed out, Dalembert grabbed the rebound, his 19th of the game, and pointed toward the sky.

They had secured a proper send-off for their former home.

"That was an exciting game on a special night," Sixers coach Tony DiLeo said. "That's the way they write it in books."

Last night, the Sixers played on the same hardwood court, refurbished this time, on which the 1983 NBA championship team played. They played in the retro uniforms they have worn in many previous games this season, but which honor the team's heritage. Above them hung the faded red championship banners from those two titles past. And in the stands sat a handful of the men who raised those banners.

One of them, Erving, whispered into Iguodala's ear before the game. He said: "Put on a show."

"That's going through my mind the first five minutes of the game," Iguodala said. "It's the whole energy and aura of the place, knowing those guys were there."

On a night dedicated to the past, we witnessed the future: Young, 21 years old, 31 points, the most scored by a Sixer this season; Iguodala, 25 years old, 25 points; Marreese Speights, 21 years old, 10 points.

Point guard Andre Miller, while not a member of these young guns, finished with 13 points, 13 assists.

It was Young's 14-point third quarter that, like a jackhammer, broke open this game. In those minutes, Young shot his trademark floater, and sliced toward the rim with a fluidity often lost in today's rough-and-tumble NBA game.

The Wachovia Center may boast the suites, the restaurants, and the fancy seating, but it might also be missing a little something: hostility.

Contact staff writer Kate Fagan at 856-779-3844 or kfagan@phillynews.com.