The Knicks then tried to show for the second straight night they also have plans for the postseason.
Joe Johnson scored 34 points and the Hawks turned back New York's late comeback to beat the Knicks 111-102 on Friday night in a game marred by a late fight.
The Knicks were handed their fifth straight road loss, a day after delivering one of their best defensive efforts in a 93-88 home win over Miami on Thursday.
"They played a great game last night and we knew they would come in with a lot of confidence," Johnson said.
Forward Marvin Williams, returning from a back injury, made his first start since Dec. 29 to give the Hawks their original starting five for the first time in almost a month. Williams may soon face an NBA suspension.
With 43.7 seconds remaining, Williams pushed New York's Shawne Williams in the back, starting a brief altercation that led to each player being ejected and charged with fighting fouls.
Shawne Williams' arms were flailing in the altercation, but he insisted he wasn't throwing punches.
"I don't know what happened, really," said Shawne Williams. "I was basically protecting myself. I was coming across half-court. He bumped me, I bumped him, and he [hit] me in the back of the head. ... I wasn't swinging at him, I was just trying to protect myself."
Marvin Williams was not made available for interviews.
The Hawks led by 24 points in the third quarter before surviving a late scare.
Amare Stoudemire led the Knicks with 27 points, including a basket to cut Atlanta's lead to 102-97 with 4:05 remaining. Josh Smith, who had 24 points, answered with a 3-pointer from the corner for Atlanta.
"It was definitely a playoff atmosphere game," Smith said.
Smith said the 50-50 split of Hawks and Knicks fans in the sellout crowd added to the intensity.
"Definitely the emotions were running high," Smith said. "It got a little chippy out there and the incident happened."
Al Horford had 19 points, 14 rebounds and six assists for Atlanta.
Marvin Williams played only 13 minutes in a backup role on Wednesday at Milwaukee in his return after missing 11 games with a lower back injury.
The altercation between Marvin Williams and Shawne Williams came shortly after Horford blocked a shot attempt by Stoudemire. The Williamses were quickly separated and each was ejected.
Marvin Williams was charged with a technical and each player was called for a fighting foul following a video review by officials.
Marvin Williams has been called for only 10 technical fouls in six NBA seasons, including none this season before Friday night, according to STATS LLC.
"I've never seen him snap like that," said Hawks coach Larry Drew of the forward. "It's an emotional game. Sometimes these things happen. Hopefully whatever the penalty is, it won't be too severe."
Stoudemire had only three rebounds as the Hawks took a 46-34 advantage on the boards.
"We didn't play hard," Stoudemire said. "We didn't play with energy. We played soft. We can't afford that. I know we're a young team, but I just hate seeing us not play hard to start the game off. We've got to do a better job of that."
The Hawks, who were held to 59 points in a loss to New Orleans in their last home game, surpassed that total in the first half, leading 60-43 at intermission.
"We came out soft and paid for it," said Knicks coach Mike D'Antoni. "If we would have played the first half the way we played the second half, we would have won this game."
The Hawks stretched the lead to 24 points in the third period. Stoudemire had eight straight points late in the period as the Knicks launched a comeback that carried over into the final period.
With 9:10 remaining in the third quarter, Marvin Williams fell backward into the back of Stoudemire's knees. Stoudemire limped off the court but soon returned.
There was no X-ray.
"It's a little sore now but we'll see how it feels tomorrow," Stoudemire said.
F Wilson Chandler (sore left calf) did not play and is listed as day to day. Shawne Williams replaced Chandler and had 12 points and 11 rebounds in only his second start of the season. ... Atlanta signed G-F Damien Wilkins for the remainder of the season. ... X-rays were negative on Hawks PG Mike Bibby's swollen left thumb. He played without a wrap or brace on the thumb. ... Singer and actress Queen Latifah attended the game as part of a crowd of 19,069, Atlanta's second sellout of the season.