Keith Urban Says Returning to 'American Idol' as a Mentor for Finale Will Be 'Incredible' (Exclusive)

Keith Urban is excited about his American Idol return.

The country musician, 55, announced last week that he will be returning to the hit ABC series for the show's season 21 finale on Sunday, where he will mentor the top three contestants and perform his song "Wild Hearts."

In an exclusive conversation with PEOPLE, Urban says he is looking forward to returning to Idol after previously serving as a judge on the competition series throughout seasons 12 to 15.

"To be able to come in as a mentor, and play as well, is incredible," he says. "That was home for me for several seasons, and the mentoring part is probably one of the things I always enjoyed the most, getting to work with the artist one-on-one."

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories.

During Idol's three-hour finale, final three contestants Iam Tongi, Megan Danielle and Colin Stough will go head-to-head to compete for the coveted title of the next American Idol.

Detailing how he thinks the three competitors are "all ready" for the finale, Urban says, "If you've made it this far, I think you're [good]."

"Most artists I've ever seen at this point have a pretty good sense of what they need to work on, what they're good at and what they're not so good at," he continues. "I think they're open to help at this point, maybe not so much early on, but by the time you get into the top three like this, I think they're all pretty receptive to good feedback."

"At the same time, I think for any artist at any level, it's knowing what advice to take and what advice to discard because it's not all accurate, no matter what somebody says," the father of two adds.

Urban tells PEOPLE that he is specifically choosing to perform his song "Wild Hearts" during the finale as a way to inspire the contestants.

"I chose it because I think it really lyrically suits the journey that these artists are all on, and getting to play on that stage with my band is going to feel great," he says.

Urban also says that the song will inspire viewers who are watching the upcoming finale at home as well.

"A lot of people who watch the show have dreams and aspirations, and they're either pursuing those or they've put them on hold, and they just need a reminder to get back on that track again," he explains. "The song is definitely an anthemic call to following your dreams, for sure."

RELATED VIDEO: Keith Urban on the Affect Johnny Cash Had on His Dad Which Inspired His New Song 'Wild Hearts'

Alongside Urban, current Idol judges Katy Perry, Lionel Richie and Luke Bryan will also take the stage on finale night to perform songs, as will this season's Top 12 contestants.

Other performers announced for the season 21 finale include Kylie Minogue, Ellie Goulding, James Blunt and Jazmine Sullivan.

Jelly Roll, Kevin Cronin from REO Speedwagon, Lainey Wilson, Lauren Daigle, Pitbull and TLC will also perform, as well as Clay Aiken and Ruben Studdard, who starred on Idol's season 2.

American Idol's season 21 finale airs live coast to coast on Sunday evening at 8 p.m. ET and 5 p.m. PT on ABC.