Collins punched the air in celebration - and the Hawks took a moment to exhale after a hefty lead was nearly squandered.
''Thank God we were up 20,'' Hawks guard Kevin Huerter said.
Young scored 25 of his 35 points in the first half as Atlanta shook off Joel Embiid and a hostile crowd and held on to beat the Philadelphia 76ers 128-124 Monday (PHT) in their Eastern Conference semifinal opener.
''The confidence in all these guys is high,'' Young said. ''We're out here playing for each other. Out here having fun. Everyone's locked in.''
Embiid raised a sledgehammer as he returned from a one-game absence with a cartilage tear in his right knee. He walked out with WWE star Triple H to a roaring ovation.
Young and the Hawks had the Sixers down for the count from the jump and led by 26 points.
The Sixers - playing in front of their biggest crowd of the season at 18,624 - refused to easily cede home court and Embiid scored consecutive baskets that brought them within three with 1:01 left.
Bogdan Bogdanovic, who missed all three games in the season series against the 76ers with a knee injury, steadied the Hawks when he buried a 3 that gave them needed breathing room.
He even put his fingers to his lips and shushed the raucous crowd for good measure.
''He's a big shot maker,'' Huerter said.
That wasn't the only long shot that went off successfully.
Going off as five-point underdogs, according to FanDuel Sportsbook, the Hawks made 14 of their first 18 buckets and were the aggressors, eagerly seizing their moment on national television. Young, much like he did in five games against the Knicks when he averaged 29.2 points, thrived in the spotlight. For all the focus on Embiid, All-Star Ben Simmons and the top-seeded Sixers, Young was the can't-miss player in Game 1 - as in, he rarely did with the ball, and all eyes were on him.
The Hawks used a 17-0 run in the first half - they hit 20 3s overall - and Young was shaking, saluting and toying with the Sixers and the crowd. Young bowed during the clincher to the New York crowd that had jeered him in every game. He stuck a pose in Philly - he held his right arm high and pointed toward the basket for several seconds that followed a 27-footer he buried to close the first half.
''They hit us in the mouth to start the game,'' 76ers coach Doc Rivers said. ''They were the more physical team. They were the more aggressive team. They played harder, early.''
Danny Green could not hang as the primary defender on Young instead of Simmons, an NBA defensive player of the year candidate.
Simmons said he wanted his shot for a full 40 minutes on Young and the Hawks expected a shift in strategy.
''Eventually, he'll see some time on a guy who's hot,'' coach Nate McMillan said.
The 6-foot-1 Young led the Hawks to the playoffs for the first time since 2017 and has craved the pressure that comes with playing big postseason games in big markets.
One Knicks fan spit on Young during the first-round series. In Philly, he heard ''Trae is balding! Trae is balding!'' chants that dimmed with each 3-pointer - he hit four 3s and had 10 assists. He waved off fans with a 3 in the third quarter that cut off a small Sixers run.
Embiid answered the will-he-or-won't-he play question when he walked out for pregame introductions in matching T-shirts with the star wrestler - Triple H's D-Generation X faction was Embiid's favorite - and had the packed house going wild as he held the sledgehammer high over his head.
Embiid did his part with 39 points and nine rebounds in 38 minutes after he suffered a small lateral meniscus tear in his right knee last Monday against Washington. Embiid, who sat out the Game 5 clincher, grimaced at times against the Hawks and hit the floor hard when he lunged at Collins and fouled him.
''Playing on a torn meniscus is not easy,'' Embiid said. ''The pain is going to be there. That's normal. It's about managing it.''
Tobias Harris had 20 points and 10 rebounds. Simmons scored 17 points and again struggled from the free-throw line, going 3 for 10.
Bogdanovic and Collins each scored 21 points for the Hawks.
Game 2 is Wednesday in Philadelphia.
The Sixers made easy work of Washington in five games and with home court throughout the East playoffs, a potential date with Brooklyn seemed in the cards. Sixers fans chanted ''We want Brooklyn'' as they wrapped a Game 5 win last week.
But they forgot about Trae.
Just 14-20 when the Hawks fired coach Lloyd Pierce on March 1, the Hawks are 33-12 since. They had the best record in the East after McMillan took over, and Young said he isn't satisfied with just one series victory.
The Sixers made them work for it in a furious fourth - but the Hawks held on and gave Atlanta sports fans something to feel good about on Sunday.
''All the individual stuff is for the birds,'' Young said. ''All we care about is wins.''
Hawks: F De'Andre Hunter sat out with a sore right knee. ... Young became the second player in NBA history to score 30 points in each of his first four career playoff road games. He joined Kareem Abdul-Jabbar of the 1970 Milwaukee Bucks. ... The Hawks scored a franchise playoff high for points in any half (74) and their 13 3-pointers in the first were a team record for a playoff half.
76ers: Were an awful 24 of 35 from the free-throw line. ... Missed 19 of 29 3-pointers.