Following his stellar dance, judges Carrie Ann Inaba, Derek Hough and Bruno Tonioli delivered their feedback, giving the team a 24/30.
"Guys, thank you for the last 27 years. Hopefully we have 27 more!" McLean shouted after tearing it up on the dance floor. "And thank you to all the fans. We love you guys!"
McLean told ET before Monday's performance that he was "over the moon grateful to my four brothers for taking time out of their schedules."
"I asked the guys, I'm like, 'This would mean the world to me. We're doing one of our songs. I'm dedicating this performance to us. It's kind of an homage to us. Would you guys be down to do it?'" he added. "They all immediately said, 'Whatever you need, buddy.' That's what family does. We all stick together."
McLean isn't the first Backstreet Boy to compete for the mirrorball. Carter finished in second place with Sharna Burgess during season 21.
Ahead of McLean's performance, he teased his virtual reunion with Carter. "Thanks @nickcarter for popping in and giving me some support and advice!!! Everybody really needs to tune into #DWTS on Monday night….there’s something BIG coming!" McLean wrote.
Carter replied, "You got this bro!! Love you! Let’s get you that mirror ball!!"
Prior to making his DWTS debut, McLean told ET that he had reached out to Carter for advice.
"I called him after the first day of rehearsal and I was like, 'Oh, boy. What did I get myself into?'" McLean revealed. "He kind of freaked me out the first time we spoke because, granted, he was going based on his experience and this is different for everybody, obviously. But he said, 'Dude, just enjoy the moment. Enjoy the process.' He's like, 'I wish I would've done a couple things differently.' He listed all these things and he's like, 'Dude, just go have fun. If anyone can do this, you can do it.'"
See more of McLean's DWTS journey in the video below. Dancing With the Stars airs Mondays at 8 p.m. on ABC.