Philadelphia led 65-33 at halftime, leading Collins to warn his players against a letdown.
"The third quarter to me was all about maturity, and I told them that," Collins said. "We weren't going to let them back in the game."
The Hawks barely won the third quarter, 25-23, but never mounted a challenge.
"[Collins] talked about it's important because later on in the season we're going to need to play that way when it's a two-point game," Brand said. "He wants to instill in us to play that way no matter the score."
The Hawks had won 14 of their last 16 at home, but this was not their first ugly loss at Philips Arena. The Hawks were held to the lowest-scoring game in Atlanta history in a 100-59 home loss to the New Orleans Hornets on Jan. 21.
It's no coincidence the Hawks were without All-Star center Al Horford in each lopsided loss. Horford missed the Jan. 21 loss with an ankle injury and was held out against the Sixers for the second straight game with a back contusion. Horford hurt his back in a fall on Friday night after a flagrant foul by the Clippers' Blake Griffin.
"Obviously, they missed Horford, but we played a terrific game tonight," Collins said. "We really played a complete game."
Zaza Pachulia started for Horford and had only two points and two rebounds.
"Obviously, nothing was working for us," Pachulia said. "There was no energy. Our shots didn't fall, and our defense wasn't there. It wasn't our day."
Atlanta coach Larry Drew tried new combinations as the Sixers' lead grew quickly, but there were no answers for Philadelphia's hot shooting on Atlanta's bench. The Sixers led 33-13 in the opening period.
The Sixers had nine steals, including three by Meeks. The 6-foot-1 Williams blocked two shots.
Drew called his team's performance "lethargic" and "totally inexcusable."
"We cannot come out and play with that type energy," Drew said.
The lone bright spot for Atlanta was rookie Jordan Crawford, who had nine points, seven rebounds and five assists in his rare opportunity for substantial playing time. Jeff Teague had 10 points.
Brand has at least 14 points in nine straight games. ... The 33 first-half points set a season low for Atlanta. The Sixers matched their season high with the 65 first-half points, also a season high for Hawks opponents. ... Horford had soreness in his back in Tuesday's shooting practice. Asked after the game how he feels, he said, "Not too good." Earlier in the day he said he expects to play on Saturday against Charlotte.